Topic 1: Stoichiometric relationships

Calculate the percentage of water by mass in the NaCl•2H₂O crystals. Use the data from section 6 of the data booklet and give your answer to two decimal places.

How many atoms of nitrogen are there in 0.50 mol of (NH₄)₂CO₃?

A. 1

B. 2

C. 3.01 × 10²³

D. 6.02 × 10²³

Calculate the concentration of ethanoic acid, CH₃COOH, in mol dm^–3.

Calculate the percentage of water by mass in the NaCl•2H₂O crystals. Use the data from section 6 of the data booklet and give your answer to two decimal places.

How many atoms of nitrogen are there in 0.50 mol of (NH₄)₂CO₃?

A. 1

B. 2

C. 3.01 × 10²³

D. 6.02 × 10²³

Calculate the percentage of water by mass in the NaCl•2H₂O crystals. Use the data from section 6 of the data booklet and give your answer to two decimal places.

Calculate the concentration of ethanoic acid, CH₃COOH, in mol dm^–3.

Calculate the concentration of ethanoic acid, CH₃COOH, in mol dm^–3.

Calculate the enthalpy change, ΔH, in kJ mol^–1, for the reaction between ethanoic acid and sodium hydroxide.

What is the value of x when 32.2 g of Na₂SO₄•xH₂O are heated leaving 14.2 g of anhydrous Na₂SO₄? M_r(H₂O) = 18; M_r(Na₂SO₄) = 142.

Na₂SO_4•xH₂O (s) → Na₂SO₄ (s) + xH₂O (g)

A. 0.1

B. 1

C. 5

D. 10

Calculate the percentage by mass of nitrogen in urea to two decimal places using section 6 of the data booklet.

What is the value of x when 32.2 g of Na₂SO₄•xH₂O are heated leaving 14.2 g of anhydrous Na₂SO₄? M_r(H₂O) = 18; M_r(Na₂SO₄) = 142.

Na₂SO_4•xH₂O (s) → Na₂SO₄ (s) + xH₂O (g)

A. 0.1

B. 1

C. 5

D. 10

How many grams of sodium azide, NaN₃, are needed to produce 68.1 dm³ of N₂ (g) at STP?

Molar volume at STP = 22.7 dm³ mol^–1; M_r(NaN₃) = 65.0

2NaN₃ (s) → 3N₂ (g) + 2Na (s)

A. 32.5

B. 65.0

C. 130.0

D. 195.0

How many grams of sodium azide, NaN₃, are needed to produce 68.1 dm³ of N₂ (g) at STP?

Molar volume at STP = 22.7 dm³ mol^–1; M_r(NaN₃) = 65.0

2NaN₃ (s) → 3N₂ (g) + 2Na (s)

A. 32.5

B. 65.0

C. 130.0

D. 195.0

What is the sum of the coefficients when the following equation is balanced using the smallest whole numbers?

__C₆H₁₂O₆ (aq) → __C₂H₅OH (aq) + __CO₂ (g)

A. 4

B. 5

C. 9

D. 10

What is the sum of the coefficients when the following equation is balanced using the smallest whole numbers?

__C₆H₁₂O₆ (aq) → __C₂H₅OH (aq) + __CO₂ (g)

A. 4

B. 5

C. 9

D. 10

Calculate the enthalpy change, ΔH, in kJ mol^–1, for the reaction between ethanoic acid and sodium hydroxide.

Calculate the enthalpy change, ΔH, in kJ mol^–1, for the reaction between ethanoic acid and sodium hydroxide.

Complete combustion of 0.1595 g of menthol produces 0.4490 g of carbon dioxide and 0.1840 g of water. Determine the empirical formula of the compound showing your working.

Complete combustion of 0.1595 g of menthol produces 0.4490 g of carbon dioxide and 0.1840 g of water. Determine the empirical formula of the compound showing your working.

Complete combustion of 0.1595 g of menthol produces 0.4490 g of carbon dioxide and 0.1840 g of water. Determine the empirical formula of the compound showing your working.

0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm³ at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.

0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm³ at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.

0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm³ at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.

Complete combustion of 0.1595 g of menthol produces 0.4490 g of carbon dioxide and 0.1840 g of water. Determine the empirical formula of the compound showing your working.

Calculate the percentage by mass of nitrogen in urea to two decimal places using section 6 of the data booklet.

Complete combustion of 0.1595 g of menthol produces 0.4490 g of carbon dioxide and 0.1840 g of water. Determine the empirical formula of the compound showing your working.

Complete combustion of 0.1595 g of menthol produces 0.4490 g of carbon dioxide and 0.1840 g of water. Determine the empirical formula of the compound showing your working.

0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm³ at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.

Which solution neutralizes 50.0 cm³ of 0.120 mol dm^–3 NaOH (aq)?

A. 12.5 cm³ of 0.080 mol dm^–3 H₃PO₄

B. 25.0 cm³ of 0.120 mol dm^–3 CH₃COOH

C. 25.0 cm³ of 0.120 mol dm^–3 H₂SO₄

D. 50.0 cm³ of 0.060 mol dm^–3 HNO₃

Which solution neutralizes 50.0 cm³ of 0.120 mol dm^–3 NaOH (aq)?

A. 12.5 cm³ of 0.080 mol dm^–3 H₃PO₄

B. 25.0 cm³ of 0.120 mol dm^–3 CH₃COOH

C. 25.0 cm³ of 0.120 mol dm^–3 H₂SO₄

D. 50.0 cm³ of 0.060 mol dm^–3 HNO₃

Calculate the percentage by mass of nitrogen in urea to two decimal places using section 6 of the data booklet.

Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH₄Cl.

KNCO(aq) + NH₄Cl(aq) → (H₂N)₂CO(aq) + KCl(aq)

Determine the maximum mass of urea that could be formed from 50.0 cm³ of 0.100 mol dm⁻³ potassium cyanate solution.

What is the pressure, in Pa, inside a 1.0 m³ cylinder containing 10 kg of H₂ (g) at 25 ºC?

R = 8.31 J K^–1 mol^–1; pV = nRT

A. $\frac{1\times {10}^4\times 8.31\times 25}{1.0\times {10}^3}$

B. $\frac{5\times {10}^2\times 8.31\times 298}{1.0}$

C. $\frac{1\times 8.31\times 25}{1.0\times {10}^3}$

D. $\frac{5\times {10}^3\times 8.31\times 298}{1.0}$

0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm³ at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.

0.150 g sample of menthol, when vaporized, had a volume of 0.0337 dm³ at 150 °C and 100.2 kPa. Calculate its molar mass showing your working.

Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH₄Cl.

KNCO(aq) + NH₄Cl(aq) → (H₂N)₂CO(aq) + KCl(aq)

Determine the maximum mass of urea that could be formed from 50.0 cm³ of 0.100 mol dm⁻³ potassium cyanate solution.

Determine the molecular formula of menthol using your answers from parts (d)(i) and (ii).

Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH₄Cl.

KNCO(aq) + NH₄Cl(aq) → (H₂N)₂CO(aq) + KCl(aq)

Determine the maximum mass of urea that could be formed from 50.0 cm³ of 0.100 mol dm⁻³ potassium cyanate solution.

The combustion of urea produces water, carbon dioxide and nitrogen.

Formulate a balanced equation for the reaction.

Determine the molecular formula of menthol using your answers from parts (d)(i) and (ii).

Determine the molecular formula of menthol using your answers from parts (d)(i) and (ii).

What is the pressure, in Pa, inside a 1.0 m³ cylinder containing 10 kg of H₂ (g) at 25 ºC?

R = 8.31 J K^–1 mol^–1; pV = nRT

A. $\frac{1\times {10}^4\times 8.31\times 25}{1.0\times {10}^3}$

B. $\frac{5\times {10}^2\times 8.31\times 298}{1.0}$

C. $\frac{1\times 8.31\times 25}{1.0\times {10}^3}$

D. $\frac{5\times {10}^3\times 8.31\times 298}{1.0}$

The combustion of urea produces water, carbon dioxide and nitrogen.

Formulate a balanced equation for the reaction.

Outline why repeating quantitative measurements is important.

The combustion of urea produces water, carbon dioxide and nitrogen.

Formulate a balanced equation for the reaction.

Calculate the maximum volume of CO₂, in cm³, produced at STP by the combustion of 0.600 g of urea, using sections 2 and 6 of the data booklet.

Outline why repeating quantitative measurements is important.

Outline why repeating quantitative measurements is important.

Calculate the maximum volume of CO₂, in cm³, produced at STP by the combustion of 0.600 g of urea, using sections 2 and 6 of the data booklet.

Calculate the percentage by mass of nitrogen in urea to two decimal places using section 6 of the data booklet.

Calculate the maximum volume of CO₂, in cm³, produced at STP by the combustion of 0.600 g of urea, using sections 2 and 6 of the data booklet.

What is the sum of the coefficients when the equation is balanced with the lowest whole number ratio?

__Na₂S₂O₃(aq) + __HCl(aq) → __S(s) + __SO₂(g) + __NaCl(aq) + __H₂O(l)

A.     6

B.     7

C.     8

D.     9

What is the sum of the coefficients when the equation is balanced with the lowest whole number ratio?

__Na₂S₂O₃(aq) + __HCl(aq) → __S(s) + __SO₂(g) + __NaCl(aq) + __H₂O(l)

A.     6

B.     7

C.     8

D.     9

Calculate the percentage by mass of nitrogen in urea to two decimal places using section 6 of the data booklet.

Calculate the percentage by mass of nitrogen in urea to two decimal places using section 6 of the data booklet.

Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH₄Cl.

                                      KNCO(aq) + NH₄Cl(aq) → (H₂N)₂CO(aq) + KCl(aq)

Determine the maximum mass of urea that could be formed from 50.0 cm³ of 0.100 mol dm⁻³ potassium cyanate solution.

Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH₄Cl.

                                      KNCO(aq) + NH₄Cl(aq) → (H₂N)₂CO(aq) + KCl(aq)

Determine the maximum mass of urea that could be formed from 50.0 cm³ of 0.100 mol dm⁻³ potassium cyanate solution.

Urea can be made by reacting potassium cyanate, KNCO, with ammonium chloride, NH₄Cl.

                                      KNCO(aq) + NH₄Cl(aq) → (H₂N)₂CO(aq) + KCl(aq)

Determine the maximum mass of urea that could be formed from 50.0 cm³ of 0.100 mol dm⁻³ potassium cyanate solution.

The combustion of urea produces water, carbon dioxide and nitrogen.

Formulate a balanced equation for the reaction.

What is the volume, in cm³, of the final solution if 100 cm³ of a solution containing 1.42 g of sodium sulfate, Na₂SO₄, is diluted to the concentration of 0.020 mol dm^–3?

M_r(Na₂SO₄) = 142

A.     50

B.     400

C.     500

D.     600

The combustion of urea produces water, carbon dioxide and nitrogen.

Formulate a balanced equation for the reaction.

The combustion of urea produces water, carbon dioxide and nitrogen.

Formulate a balanced equation for the reaction.

What is the volume, in cm³, of the final solution if 100 cm³ of a solution containing 1.42 g of sodium sulfate, Na₂SO₄, is diluted to the concentration of 0.020 mol dm^–3?

M_r(Na₂SO₄) = 142

A.     50

B.     400

C.     500

D.     600

The solution of palmitic acid had a concentration of 0.0034 mol dm⁻³. Calculate the number of molecules of palmitic acid present in the 0.050 cm³ drop, using section 2 of the data booklet.

The solution of palmitic acid had a concentration of 0.0034 mol dm⁻³. Calculate the number of molecules of palmitic acid present in the 0.050 cm³ drop, using section 2 of the data booklet.

The solution of palmitic acid had a concentration of 0.0034 mol dm⁻³. Calculate the number of molecules of palmitic acid present in the 0.050 cm³ drop, using section 2 of the data booklet.

Assuming the sudden change in gradient occurs at 240 cm², calculate the area, in cm², that a single molecule of palmitic acid occupies on surface of the water.

If you did not obtain an answer for (b)(ii) use a value of 8.2 × 10¹⁶, but this is not the correct answer.

What is the percentage yield when 2.0 g of ethene, C₂H₄, is formed from 5.0 g of ethanol, C₂H₅OH?
M_r(ethene) = 28; M_r(ethanol) = 46

A.     $\frac{2.0}{28}\times \frac{5.0}{46}\times 100$

B.     $\frac{\frac{2.0}{28}}{\frac{5.0}{46}}\times 100$

C.     $\frac{28}{2.0}\times \frac{5.0}{46}\times 100$

D.     $\frac{\frac{28}{2.0}}{\frac{5.0}{46}}\times 100$

Assuming the sudden change in gradient occurs at 240 cm², calculate the area, in cm², that a single molecule of palmitic acid occupies on surface of the water.

If you did not obtain an answer for (b)(ii) use a value of 8.2 × 10¹⁶, but this is not the correct answer.

Assuming the sudden change in gradient occurs at 240 cm², calculate the area, in cm², that a single molecule of palmitic acid occupies on surface of the water.

If you did not obtain an answer for (b)(ii) use a value of 8.2 × 10¹⁶, but this is not the correct answer.

Annotate the balanced equation below with state symbols.

CaCO₃(__) + 2HCl(__) → CaCl₂(__) + CO₂(__) + H₂O(__)

What is the percentage yield when 2.0 g of ethene, C₂H₄, is formed from 5.0 g of ethanol, C₂H₅OH?
M_r(ethene) = 28; M_r(ethanol) = 46

A.     $\frac{2.0}{28}\times \frac{5.0}{46}\times 100$

B.     $\frac{\frac{2.0}{28}}{\frac{5.0}{46}}\times 100$

C.     $\frac{28}{2.0}\times \frac{5.0}{46}\times 100$

D.     $\frac{\frac{28}{2.0}}{\frac{5.0}{46}}\times 100$

Annotate the balanced equation below with state symbols.

CaCO₃(__) + 2HCl(__) → CaCl₂(__) + CO₂(__) + H₂O(__)

Annotate the balanced equation below with state symbols.

CaCO₃(__) + 2HCl(__) → CaCl₂(__) + CO₂(__) + H₂O(__)

What is the percentage yield when 7 g of ethene produces 6 g of ethanol?

M_r(ethene) = 28 and M_r(ethanol) = 46

C₂H₄(g) + H₂O(g) → C₂H₅OH(g)

A.     $\frac{6\times 7\times 100}{28\times 46}$

B.     $\frac{6\times 46\times 100}{7\times 28}$

C.     $\frac{6\times 28}{7\times 46\times 100}$

D.     $\frac{6\times 28\times 100}{7\times 46}$

Calculate the amount, in mol, of H₂SO₄.

How many moles of FeS₂ are required to produce 32 g of SO₂? (A_r: S = 32, O = 16)

4FeS₂ (s) + 11O₂ (g) → 2Fe₂O₃ (s) + 8SO₂ (g)

A.   0.25

B.   0.50

C.   1.0

D.   2.0

Calculate the amount, in mol, of H₂SO₄.

Calculate the amount, in mol, of H₂SO₄.

Formulate the equation for the reaction of H₂SO₄ with Mg(OH)₂.

Formulate the equation for the reaction of H₂SO₄ with Mg(OH)₂.

Formulate the equation for the reaction of H₂SO₄ with Mg(OH)₂.

The excess sulfuric acid required 20.80 cm³ of 0.1133 mol dm⁻³ NaOH for neutralization.

Calculate the amount of excess acid present.

The excess sulfuric acid required 20.80 cm³ of 0.1133 mol dm⁻³ NaOH for neutralization.

Calculate the amount of excess acid present.

The excess sulfuric acid required 20.80 cm³ of 0.1133 mol dm⁻³ NaOH for neutralization.

Calculate the amount of excess acid present.

Calculate the amount of H₂SO₄ that reacted with Mg(OH)₂.

What is the percentage yield when 7 g of ethene produces 6 g of ethanol?

M_r(ethene) = 28 and M_r(ethanol) = 46

C₂H₄(g) + H₂O(g) → C₂H₅OH(g)

A.     $\frac{6\times 7\times 100}{28\times 46}$

B.     $\frac{6\times 46\times 100}{7\times 28}$

C.     $\frac{6\times 28}{7\times 46\times 100}$

D.     $\frac{6\times 28\times 100}{7\times 46}$

How many moles of FeS₂ are required to produce 32 g of SO₂? (A_r: S = 32, O = 16)

4FeS₂ (s) + 11O₂ (g) → 2Fe₂O₃ (s) + 8SO₂ (g)

A.   0.25

B.   0.50

C.   1.0

D.   2.0

Determine the limiting reactant showing your working.

Calculate the amount of H₂SO₄ that reacted with Mg(OH)₂.

Calculate the amount of H₂SO₄ that reacted with Mg(OH)₂.

Determine the mass of Mg(OH)₂ in the antacid tablet.

Determine the mass of Mg(OH)₂ in the antacid tablet.

Determine the mass of Mg(OH)₂ in the antacid tablet.

Calculate the percentage by mass of magnesium hydroxide in the 1.24 g antacid tablet to three significant figures.

Determine the limiting reactant showing your working.

Determine the limiting reactant showing your working.

The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.

Calculate the percentage by mass of magnesium hydroxide in the 1.24 g antacid tablet to three significant figures.

Calculate the percentage by mass of magnesium hydroxide in the 1.24 g antacid tablet to three significant figures.

16 g of bromine react with 5.2 g of metal, M, to form MBr₂. What is the relative atomic mass of the metal M? (A_r : Br = 80)

A.   13

B.   26

C.   52

D.   104

16 g of bromine react with 5.2 g of metal, M, to form MBr₂. What is the relative atomic mass of the metal M? (A_r : Br = 80)

A.   13

B.   26

C.   52

D.   104

The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.

The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.

An antacid tablet containing 0.50 g of NaHCO₃ (M_r = 84) is dissolved in water to give a volume of 250 cm³. What is the concentration, in mol dm⁻³, of HCO₃⁻ in this solution?

A.   $\frac{0.250\times 84}{0.50}$

B.   $\frac{0.50}{84\times 0.250}$

C.   $\frac{250\times 84}{0.50}$

D.   $\frac{0.50}{84\times 250}$

Determine the limiting reactant showing your working.

An antacid tablet containing 0.50 g of NaHCO₃ (M_r = 84) is dissolved in water to give a volume of 250 cm³. What is the concentration, in mol dm⁻³, of HCO₃⁻ in this solution?

A.   $\frac{0.250\times 84}{0.50}$

B.   $\frac{0.50}{84\times 0.250}$

C.   $\frac{250\times 84}{0.50}$

D.   $\frac{0.50}{84\times 250}$

Determine the limiting reactant showing your working.

Determine the limiting reactant showing your working.

Outline how a solution of 0.0100 mol dm⁻³ is obtained from a standard 1.000 mol dm⁻³ copper(II) sulfate solution, including two essential pieces of glassware you would need.

The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.

The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.

The mass of copper obtained experimentally was 0.872 g. Calculate the percentage yield of copper.

Outline how a solution of 0.0100 mol dm⁻³ is obtained from a standard 1.000 mol dm⁻³ copper(II) sulfate solution, including two essential pieces of glassware you would need.

Determine the empirical formula of the compound, showing your working.

Outline how a solution of 0.0100 mol dm⁻³ is obtained from a standard 1.000 mol dm⁻³ copper(II) sulfate solution, including two essential pieces of glassware you would need.

Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na₂S₂O₃ (aq). Copper(I) iodide is a white solid.

4I⁻ (aq) + 2Cu²⁺ (aq) → 2CuI (s) + I₂ (aq)

I₂ (aq) + 2S₂O₃²⁻ (aq) → 2I⁻ (aq) + S₄O₆²⁻ (aq)

Deduce the overall equation for the two reactions by combining the two equations.

Determine the empirical formula of the compound, showing your working.

Determine the empirical formula of the compound, showing your working.

Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na₂S₂O₃ (aq). Copper(I) iodide is a white solid.

4I⁻ (aq) + 2Cu²⁺ (aq) → 2CuI (s) + I₂ (aq)

I₂ (aq) + 2S₂O₃²⁻ (aq) → 2I⁻ (aq) + S₄O₆²⁻ (aq)

Deduce the overall equation for the two reactions by combining the two equations.

Calculate the number of hydrogen atoms in 1.00 g of propan-2-ol.

Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na₂S₂O₃ (aq). Copper(I) iodide is a white solid.

4I⁻ (aq) + 2Cu²⁺ (aq) → 2CuI (s) + I₂ (aq)

I₂ (aq) + 2S₂O₃²⁻ (aq) → 2I⁻ (aq) + S₄O₆²⁻ (aq)

Deduce the overall equation for the two reactions by combining the two equations.

Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.

Outline how a solution of 0.0100 mol dm⁻³ is obtained from a standard 1.000 mol dm⁻³ copper(II) sulfate solution, including two essential pieces of glassware you would need.

Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.

Outline how a solution of 0.0100 mol dm⁻³ is obtained from a standard 1.000 mol dm⁻³ copper(II) sulfate solution, including two essential pieces of glassware you would need.

Outline how a solution of 0.0100 mol dm⁻³ is obtained from a standard 1.000 mol dm⁻³ copper(II) sulfate solution, including two essential pieces of glassware you would need.

Calculate the number of hydrogen atoms in 1.00 g of propan-2-ol.

Calculate the number of hydrogen atoms in 1.00 g of propan-2-ol.

Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

Titration is another method for analysing the solution obtained from adding brass to nitric acid.

Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na₂S₂O₃ (aq). Copper(I) iodide is a white solid.

4I⁻ (aq) + 2Cu²⁺ (aq) → 2CuI (s) + I₂ (aq)

I₂ (aq) + 2S₂O₃²⁻ (aq) → 2I⁻ (aq) + S₄O₆²⁻ (aq)

Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.

Titration is another method for analysing the solution obtained from adding brass to nitric acid.

Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na₂S₂O₃ (aq). Copper(I) iodide is a white solid.

4I⁻ (aq) + 2Cu²⁺ (aq) → 2CuI (s) + I₂ (aq)

I₂ (aq) + 2S₂O₃²⁻ (aq) → 2I⁻ (aq) + S₄O₆²⁻ (aq)

Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.

Titration is another method for analysing the solution obtained from adding brass to nitric acid.

Copper(II) ions are reduced to copper(I) iodide by the addition of potassium iodide solution, releasing iodine that can be titrated with sodium thiosulfate solution, Na₂S₂O₃ (aq). Copper(I) iodide is a white solid.

4I⁻ (aq) + 2Cu²⁺ (aq) → 2CuI (s) + I₂ (aq)

I₂ (aq) + 2S₂O₃²⁻ (aq) → 2I⁻ (aq) + S₄O₆²⁻ (aq)

Suggest why the end point of the titration is difficult to determine, even with the addition of starch to turn the remaining free iodine black.

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

Explain why, as the reaction proceeds, the pressure increases by the amount shown.

Sodium percarbonate, 2Na₂CO₃•3H₂O₂, is an adduct of sodium carbonate and hydrogen peroxide and is used as a cleaning agent.

M_r (2Na₂CO₃•3H₂O₂) = 314.04

Calculate the percentage by mass of hydrogen peroxide in sodium percarbonate, giving your answer to two decimal places.

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

Sodium peroxide, Na₂O₂, is formed by the reaction of sodium oxide with oxygen.

2Na₂O (s) + O₂ (g) → 2Na₂O₂ (s)

Calculate the percentage yield of sodium peroxide if 5.00g of sodium oxide produces 5.50g of sodium peroxide.

Sodium percarbonate, 2Na₂CO₃•3H₂O₂, is an adduct of sodium carbonate and hydrogen peroxide and is used as a cleaning agent.

M_r (2Na₂CO₃•3H₂O₂) = 314.04

Calculate the percentage by mass of hydrogen peroxide in sodium percarbonate, giving your answer to two decimal places.

Sodium percarbonate, 2Na₂CO₃•3H₂O₂, is an adduct of sodium carbonate and hydrogen peroxide and is used as a cleaning agent.

M_r (2Na₂CO₃•3H₂O₂) = 314.04

Calculate the percentage by mass of hydrogen peroxide in sodium percarbonate, giving your answer to two decimal places.

A sample of gas was enriched to contain 2 % by mass of ¹⁵N with the remainder being ¹⁴N.

Calculate the relative molecular mass of the resulting N₂O.

Explain why, as the reaction proceeds, the pressure increases by the amount shown.

Explain why, as the reaction proceeds, the pressure increases by the amount shown.

The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.

Sketch, on the axes in question 2, the graph that you would expect.

The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.

Sketch, on the axes in question 2, the graph that you would expect.

The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.

Sketch, on the axes in question 2, the graph that you would expect.

Sodium peroxide, Na₂O₂, is formed by the reaction of sodium oxide with oxygen.

2Na₂O (s) + O₂ (g) → 2Na₂O₂ (s)

Calculate the percentage yield of sodium peroxide if 5.00g of sodium oxide produces 5.50g of sodium peroxide.

A mean daily lead intake of greater than 5.0 × 10⁻⁶ g per kg of body weight results in increased lead levels in the body.

Calculate the volume, in dm³, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.

A mean daily lead intake of greater than 5.0 × 10⁻⁶ g per kg of body weight results in increased lead levels in the body.

Calculate the volume, in dm³, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.

A mean daily lead intake of greater than 5.0 × 10⁻⁶ g per kg of body weight results in increased lead levels in the body.

Calculate the volume, in dm³, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.

A sample of gas was enriched to contain 2 % by mass of ¹⁵N with the remainder being ¹⁴N.

Calculate the relative molecular mass of the resulting N₂O.

A sample of gas was enriched to contain 2 % by mass of ¹⁵N with the remainder being ¹⁴N.

Calculate the relative molecular mass of the resulting N₂O.

Sodium peroxide, Na₂O₂, is formed by the reaction of sodium oxide with oxygen.

2Na₂O (s) + O₂ (g) → 2Na₂O₂ (s)

Calculate the percentage yield of sodium peroxide if 5.00g of sodium oxide produces 5.50g of sodium peroxide.

Outline why a real gas differs from ideal behaviour at low temperature and high pressure.

Calculate the percentage, by mass, of rhenium in ReCl₃.

Calculate the percentage, by mass, of rhenium in ReCl₃.

Calculate the percentage, by mass, of rhenium in ReCl₃.

Outline why a real gas differs from ideal behaviour at low temperature and high pressure.

100.0cm³ of soda water contains 3.0 × 10⁻²g NaHCO₃.

Calculate the concentration of NaHCO₃ in mol dm⁻³.

Outline why a real gas differs from ideal behaviour at low temperature and high pressure.

The reaction of sodium peroxide with excess water produces hydrogen peroxide and one other sodium compound. Suggest the formula of this compound.

100.0cm³ of soda water contains 3.0 × 10⁻²g NaHCO₃.

Calculate the concentration of NaHCO₃ in mol dm⁻³.

100.0cm³ of soda water contains 3.0 × 10⁻²g NaHCO₃.

Calculate the concentration of NaHCO₃ in mol dm⁻³.

What volume of carbon dioxide, CO₂ (g), can be obtained by reacting 1 dm³ of methane, CH₄ (g), with 1 dm³ of oxygen, O₂ (g)?

CH₄ (g) + 2O₂ (g) → CO₂ (g) + 2H₂O (l)

A. 0.5 dm³

B. 1 dm³

C. 2 dm³

D. 6 dm³

The reaction of sodium peroxide with excess water produces hydrogen peroxide and one other sodium compound. Suggest the formula of this compound.

What volume of carbon dioxide, CO₂ (g), can be obtained by reacting 1 dm³ of methane, CH₄ (g), with 1 dm³ of oxygen, O₂ (g)?

CH₄ (g) + 2O₂ (g) → CO₂ (g) + 2H₂O (l)

A. 0.5 dm³

B. 1 dm³

C. 2 dm³

D. 6 dm³

Deduce, giving a reason, the group of elements in the periodic table most likely to undergo sublimation.

Deduce, giving a reason, the group of elements in the periodic table most likely to undergo sublimation.

Deduce, giving a reason, the group of elements in the periodic table most likely to undergo sublimation.

The reaction of sodium peroxide with excess water produces hydrogen peroxide and one other sodium compound. Suggest the formula of this compound.

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

How many moles of magnesium hydroxide are produced with 0.50 mol of ammonia?

Mg₃N₂ (s) + 6H₂O (l) → 3Mg(OH)₂ (aq) + 2NH₃ (aq)

A. 0.25

B. 0.33

C. 0.75

D. 1.5

How many moles of magnesium hydroxide are produced with 0.50 mol of ammonia?

Mg₃N₂ (s) + 6H₂O (l) → 3Mg(OH)₂ (aq) + 2NH₃ (aq)

A. 0.25

B. 0.33

C. 0.75

D. 1.5

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

Explain why, as the reaction proceeds, the pressure increases by the amount shown.

Explain why, as the reaction proceeds, the pressure increases by the amount shown.

Explain why, as the reaction proceeds, the pressure increases by the amount shown.

What is the sum of the integer coefficients when propene undergoes complete combustion?

__C₃H₆ (g) + __O₂ (g) → __CO₂ (g) + __H₂O (l)

A. 11

B. 17

C. 21

D. 23

Formulate the equation for the complete combustion of benzoic acid in oxygen using only integer coefficients.

Sodium peroxide, Na₂O₂, is formed by the reaction of sodium oxide with oxygen.

2Na₂O (s) + O₂ (g) → 2Na₂O₂ (s)

Calculate the percentage yield of sodium peroxide if 5.00 g of sodium oxide produces 5.50 g of sodium peroxide.

What is the sum of the integer coefficients when propene undergoes complete combustion?

__C₃H₆ (g) + __O₂ (g) → __CO₂ (g) + __H₂O (l)

A. 11

B. 17

C. 21

D. 23

The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.

Sketch, on the axes in question 2, the graph that you would expect.

The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.

Sketch, on the axes in question 2, the graph that you would expect.

The experiment is repeated using the same amount of dinitrogen monoxide in the same apparatus, but at a lower temperature.

Sketch, on the axes in question 2, the graph that you would expect.

Sodium peroxide, Na₂O₂, is formed by the reaction of sodium oxide with oxygen.

2Na₂O (s) + O₂ (g) → 2Na₂O₂ (s)

Calculate the percentage yield of sodium peroxide if 5.00 g of sodium oxide produces 5.50 g of sodium peroxide.

A sample of gas was enriched to contain 2 % by mass of ¹⁵N with the remainder being ¹⁴N.

Calculate the relative molecular mass of the resulting N₂O.

A mean daily lead intake of greater than 5.0 × 10⁻⁶ g per kg of body weight results in increased lead levels in the body.

Calculate the volume, in dm³, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.

A mean daily lead intake of greater than 5.0 × 10⁻⁶ g per kg of body weight results in increased lead levels in the body.

Calculate the volume, in dm³, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.

A mean daily lead intake of greater than 5.0 × 10⁻⁶ g per kg of body weight results in increased lead levels in the body.

Calculate the volume, in dm³, of tap water from experiment 8 which would exceed this daily lead intake for an 80.0 kg man.

Sodium peroxide, Na₂O₂, is formed by the reaction of sodium oxide with oxygen.

2Na₂O (s) + O₂ (g) → 2Na₂O₂ (s)

Calculate the percentage yield of sodium peroxide if 5.00 g of sodium oxide produces 5.50 g of sodium peroxide.

The reaction of sodium peroxide with excess water produces hydrogen peroxide and one other sodium compound. Suggest the formula of this compound.

Describe the characteristics of the nematic liquid crystal phase and the effect that an electric field has on it.

Shape of molecules:

Distribution:

Effect of electric field:

Describe the characteristics of the nematic liquid crystal phase and the effect that an electric field has on it.

Shape of molecules:

Distribution:

Effect of electric field:

A sample of gas was enriched to contain 2 % by mass of ¹⁵N with the remainder being ¹⁴N.

Calculate the relative molecular mass of the resulting N₂O.

A sample of gas was enriched to contain 2 % by mass of ¹⁵N with the remainder being ¹⁴N.

Calculate the relative molecular mass of the resulting N₂O.

The reaction of sodium peroxide with excess water produces hydrogen peroxide and one other sodium compound. Suggest the formula of this compound.

100.0 cm³ of soda water contains 3.0 × 10⁻² g NaHCO₃.

Calculate the concentration of NaHCO₃ in mol dm⁻³.

The reaction of sodium peroxide with excess water produces hydrogen peroxide and one other sodium compound. Suggest the formula of this compound.

Sodium percarbonate, 2Na₂CO₃•3H₂O₂, is an adduct of sodium carbonate and hydrogen peroxide and is used as a cleaning agent.

M_r (2Na₂CO₃•3H₂O₂) = 314.04

Calculate the percentage by mass of hydrogen peroxide in sodium percarbonate, giving your answer to two decimal places.

Sodium percarbonate, 2Na₂CO₃•3H₂O₂, is an adduct of sodium carbonate and hydrogen peroxide and is used as a cleaning agent.

M_r (2Na₂CO₃•3H₂O₂) = 314.04

Calculate the percentage by mass of hydrogen peroxide in sodium percarbonate, giving your answer to two decimal places.

100.0 cm³ of soda water contains 3.0 × 10⁻² g NaHCO₃.

Calculate the concentration of NaHCO₃ in mol dm⁻³.

100.0 cm³ of soda water contains 3.0 × 10⁻² g NaHCO₃.

Calculate the concentration of NaHCO₃ in mol dm⁻³.

Deduce, giving a reason, the group of elements in the periodic table most likely to undergo sublimation.

Sodium percarbonate, 2Na₂CO₃•3H₂O₂, is an adduct of sodium carbonate and hydrogen peroxide and is used as a cleaning agent.

M_r (2Na₂CO₃•3H₂O₂) = 314.04

Calculate the percentage by mass of hydrogen peroxide in sodium percarbonate, giving your answer to two decimal places.

What is the sum of the coefficients when the equation is balanced with the smallest whole numbers?

__BaCl₂ (aq) + __Fe₂(SO₄)₃ (aq) → __FeCl₃ (aq) + __BaSO₄ (s)

A. 4

B. 6

C. 8

D. 9

What is the sum of the coefficients when the equation is balanced with the smallest whole numbers?

__BaCl₂ (aq) + __Fe₂(SO₄)₃ (aq) → __FeCl₃ (aq) + __BaSO₄ (s)

A. 4

B. 6

C. 8

D. 9

Which graph would not show a linear relationship for a fixed mass of an ideal gas with all other variables constant?

A. P against V

B. P against $\frac{1}{\text{V}}$

C. P against T

D. V against T

Which graph would not show a linear relationship for a fixed mass of an ideal gas with all other variables constant?

A. P against V

B. P against $\frac{1}{\text{V}}$

C. P against T

D. V against T

How many moles of magnesium hydroxide are produced with 0.50 mol of ammonia?

Mg₃N₂ (s) + 6H₂O (l) → 3Mg(OH)₂ (aq) + 2NH₃ (aq)

A. 0.25

B. 0.33

C. 0.75

D. 1.5

How many moles of magnesium hydroxide are produced with 0.50 mol of ammonia?

Mg₃N₂ (s) + 6H₂O (l) → 3Mg(OH)₂ (aq) + 2NH₃ (aq)

A. 0.25

B. 0.33

C. 0.75

D. 1.5

What is the sum of the integer coefficients when propene undergoes complete combustion?

__C₃H₆ (g) + __O₂ (g) → __CO₂ (g) + __H₂O (l)

A. 11

B. 17

C. 21

D. 23

What is the sum of the integer coefficients when propene undergoes complete combustion?

__C₃H₆ (g) + __O₂ (g) → __CO₂ (g) + __H₂O (l)

A. 11

B. 17

C. 21

D. 23

What is the volume of gas when the pressure on 100 cm³ of gas is changed from 400 kPa to 200 kPa at constant temperature?

A. 50.0 cm³

B. 100 cm³

C. 200 cm³

D. 800 cm³

What is the volume of gas when the pressure on 100 cm³ of gas is changed from 400 kPa to 200 kPa at constant temperature?

A. 50.0 cm³

B. 100 cm³

C. 200 cm³

D. 800 cm³

What is the concentration, in mol dm⁻³, of 20.0 g of NaOH (M_r = 40.0) in 500.0 cm³?

A. 0.250

B. 0.500

C. 1.00

D. 4.00

Deduce, giving a reason, the group of elements in the periodic table most likely to undergo sublimation.

Deduce, giving a reason, the group of elements in the periodic table most likely to undergo sublimation.

What is the concentration, in mol dm⁻³, of 20.0 g of NaOH (M_r = 40.0) in 500.0 cm³?

A. 0.250

B. 0.500

C. 1.00

D. 4.00

Calculate the number of moles of oxygen in the day 0 sample.

Calculate the number of moles of oxygen in the day 0 sample.

Calculate the number of moles of oxygen in the day 0 sample.

The day 5 sample contained 5.03 × 10⁻⁵ moles of oxygen.

Determine the 5-day biochemical oxygen demand of the pond, in mg dm⁻³ (“parts per million”, ppm).

Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl₂•$x$H₂O.

A student heated a sample of hydrated copper(II) chloride, in order to determine the value of $x$. The following results were obtained:

Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 g

Determine the value of $x$.

The day 5 sample contained 5.03 × 10⁻⁵ moles of oxygen.

Determine the 5-day biochemical oxygen demand of the pond, in mg dm⁻³ (“parts per million”, ppm).

The day 5 sample contained 5.03 × 10⁻⁵ moles of oxygen.

Determine the 5-day biochemical oxygen demand of the pond, in mg dm⁻³ (“parts per million”, ppm).

Write an equation for the complete combustion of the compound C₃H₈O formed in (a)(iv).

Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl₂•$x$H₂O.

A student heated a sample of hydrated copper(II) chloride, in order to determine the value of $x$. The following results were obtained:

Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 g

Determine the value of $x$.

Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl₂•$x$H₂O.

A student heated a sample of hydrated copper(II) chloride, in order to determine the value of $x$. The following results were obtained:

Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 g

Determine the value of $x$.

Deduce the equation for the decomposition of guanidinium nitrate.

Write an equation for the complete combustion of the compound C₃H₈O formed in (a)(iv).

Write the half-equation for the formation of gas bubbles at electrode 1.

Write an equation for the complete combustion of the compound C₃H₈O formed in (a)(iv).

Deduce the equation for the decomposition of guanidinium nitrate.

Deduce the equation for the decomposition of guanidinium nitrate.

Write the half-equation for the formation of gas bubbles at electrode 1.

Write the half-equation for the formation of gas bubbles at electrode 1.

1.40 × 10⁻³ g of NaOH (s) are dissolved in 250.0 cm³ of 1.00 × 10⁻¹¹ mol dm⁻³ Pb(OH)₂ (aq) solution.

Determine the change in lead ion concentration in the solution, using section 32 of the data booklet.

Calculate the total number of moles of gas produced from the decomposition of 10.0 g of guanidinium nitrate.

1.40 × 10⁻³ g of NaOH (s) are dissolved in 250.0 cm³ of 1.00 × 10⁻¹¹ mol dm⁻³ Pb(OH)₂ (aq) solution.

Determine the change in lead ion concentration in the solution, using section 32 of the data booklet.

Calculate the pH of a buffer solution which contains 0.20 mol dm⁻³ ethanoic acid and 0.50 mol dm⁻³ sodium ethanoate. Use section 1 of the data booklet.

pK_a (ethanoic acid) = 4.76

Calculate the total number of moles of gas produced from the decomposition of 10.0 g of guanidinium nitrate.

Calculate the total number of moles of gas produced from the decomposition of 10.0 g of guanidinium nitrate.

Deduce the half-equation for the formation of the gas identified in (c)(iii).

Calculate the pH of a buffer solution which contains 0.20 mol dm⁻³ ethanoic acid and 0.50 mol dm⁻³ sodium ethanoate. Use section 1 of the data booklet.

pK_a (ethanoic acid) = 4.76

Calculate the pressure, in kPa, of this gas in a 10.0 dm³ air bag at 127°C, assuming no gas escapes.

Calculate the pH of a buffer solution which contains 0.20 mol dm⁻³ ethanoic acid and 0.50 mol dm⁻³ sodium ethanoate. Use section 1 of the data booklet.

pK_a (ethanoic acid) = 4.76

0.10 mol of hydrochloric acid is mixed with 0.10 mol of calcium carbonate.

2HCl (aq) + CaCO₃ (s) → CaCl₂ (aq) + H₂O (l) + CO₂ (g)

Which is correct?

Calculate the pressure, in kPa, of this gas in a 10.0 dm³ air bag at 127°C, assuming no gas escapes.

Calculate the pressure, in kPa, of this gas in a 10.0 dm³ air bag at 127°C, assuming no gas escapes.

Deduce the half-equation for the formation of the gas identified in (c)(iii).

Deduce the half-equation for the formation of the gas identified in (c)(iii).

0.10 mol of hydrochloric acid is mixed with 0.10 mol of calcium carbonate.

2HCl (aq) + CaCO₃ (s) → CaCl₂ (aq) + H₂O (l) + CO₂ (g)

Which is correct?

Write an equation for the reaction of C₂H₅Cl with aqueous sodium hydroxide to produce a C₂H₆O compound, showing structural formulas.

What is the sum of the coefficients when the equation is balanced with whole numbers?

__MnO₂ (s) + __HCl (aq) → __MnCl₂ (aq) + __H₂O (l) + __Cl₂ (g)

A.  6

B.  7

C.  8

D.  9

Another airbag reactant produces nitrogen gas and sodium.

Suggest, including an equation, why the products of this reactant present a safety hazard.

Another airbag reactant produces nitrogen gas and sodium.

Suggest, including an equation, why the products of this reactant present a safety hazard.

Another airbag reactant produces nitrogen gas and sodium.

Suggest, including an equation, why the products of this reactant present a safety hazard.

Write an equation for the reaction of C₂H₅Cl with aqueous sodium hydroxide to produce a C₂H₆O compound, showing structural formulas.

Write an equation for the reaction of C₂H₅Cl with aqueous sodium hydroxide to produce a C₂H₆O compound, showing structural formulas.

What is the sum of the coefficients when the equation is balanced with whole numbers?

__MnO₂ (s) + __HCl (aq) → __MnCl₂ (aq) + __H₂O (l) + __Cl₂ (g)

A.  6

B.  7

C.  8

D.  9

Write an equation for the complete combustion of the organic product in (b).

Write an equation for the complete combustion of the organic product in (b).

Write an equation for the complete combustion of the organic product in (b).

Which contains the greatest number of moles of oxygen atoms?

A.  0.05 mol Mg(NO₃)₂

B.  0.05 mol C₆H₄(NO₂)₂

C.  0.1 mol H₂O

D.  0.1 mol NO₂

Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl₂•$x$H₂O.

A student heated a sample of hydrated copper(II) chloride, in order to determine the value of $x$. The following results were obtained:

Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 g

Determine the value of $x$.

Which contains the greatest number of moles of oxygen atoms?

A.  0.05 mol Mg(NO₃)₂

B.  0.05 mol C₆H₄(NO₂)₂

C.  0.1 mol H₂O

D.  0.1 mol NO₂

Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl₂•$x$H₂O.

A student heated a sample of hydrated copper(II) chloride, in order to determine the value of $x$. The following results were obtained:

Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 g

Determine the value of $x$.

Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl₂•$x$H₂O.

A student heated a sample of hydrated copper(II) chloride, in order to determine the value of $x$. The following results were obtained:

Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 g

Determine the value of $x$.

What is the molar mass, in $\mathrm{g} {\mathrm{mol}}^{-1}$, of a compound if $0.200 \mathrm{mol}$ of the compound has a mass of $13.2 \mathrm{g}$?

A.  $66.0$

B.  $66$

C.  $26.4$

D.  $26$

Write the half-equation for the formation of gas bubbles at electrode 1.

Write the half-equation for the formation of gas bubbles at electrode 1.

Write the half-equation for the formation of gas bubbles at electrode 1.

What is the molar mass, in $\mathrm{g} {\mathrm{mol}}^{-1}$, of a compound if $0.200 \mathrm{mol}$ of the compound has a mass of $13.2 \mathrm{g}$?

A.  $66.0$

B.  $66$

C.  $26.4$

D.  $26$

What is the number of carbon atoms in $12 \mathrm{g}$ of ethanoic acid ${\mathrm{CH}}_3\mathrm{COOH}$, $M_{\mathrm{r}}=60$?

A.  $0.20$

B.  $2.0$

C.  $1.2\times {10}^{23}$

D.  $2.4\times {10}^{23}$

Calculate the amount, in $\mathrm{mol}$, of manganese(IV) oxide added.

What is the number of carbon atoms in $12 \mathrm{g}$ of ethanoic acid ${\mathrm{CH}}_3\mathrm{COOH}$, $M_{\mathrm{r}}=60$?

A.  $0.20$

B.  $2.0$

C.  $1.2\times {10}^{23}$

D.  $2.4\times {10}^{23}$

Which of these molecular formulae are also empirical formulae?

1.  ${\mathrm{C}}_2{\mathrm{H}}_6\mathrm{O}$
2.  ${\mathrm{C}}_2{\mathrm{H}}_4{\mathrm{O}}_2$
3.  ${\mathrm{C}}_5{\mathrm{H}}_{12}$

A.  I and II only

B.  I and III only

C.  II and III only

D.  I, II and III

Which of these molecular formulae are also empirical formulae?

1.  ${\mathrm{C}}_2{\mathrm{H}}_6\mathrm{O}$
2.  ${\mathrm{C}}_2{\mathrm{H}}_4{\mathrm{O}}_2$
3.  ${\mathrm{C}}_5{\mathrm{H}}_{12}$

A.  I and II only

B.  I and III only

C.  II and III only

D.  I, II and III

Calculate the amount, in $\mathrm{mol}$, of manganese(IV) oxide added.

Calculate the amount, in $\mathrm{mol}$, of manganese(IV) oxide added.

Write the equation for the reaction of chloroethane with a dilute aqueous solution of sodium hydroxide.

Which volume of ethane gas, in ${\mathrm{cm}}^3$, will produce $40 {\mathrm{cm}}^3$ of carbon dioxide gas when mixed with $140 {\mathrm{cm}}^3$ of oxygen gas, assuming the reaction goes to completion?

$2{\mathrm{C}}_2{\mathrm{H}}_6 \left(\mathrm{g}\right)+7{\mathrm{O}}_2 \left(\mathrm{g}\right)\to 4{\mathrm{CO}}_2 \left(\mathrm{g}\right)+6{\mathrm{H}}_2\mathrm{O} \left(\mathrm{g}\right)$

A.  $10$

B.  $20$

C.  $40$

D.  $80$

Which volume of ethane gas, in ${\mathrm{cm}}^3$, will produce $40 {\mathrm{cm}}^3$ of carbon dioxide gas when mixed with $140 {\mathrm{cm}}^3$ of oxygen gas, assuming the reaction goes to completion?

$2{\mathrm{C}}_2{\mathrm{H}}_6 \left(\mathrm{g}\right)+7{\mathrm{O}}_2 \left(\mathrm{g}\right)\to 4{\mathrm{CO}}_2 \left(\mathrm{g}\right)+6{\mathrm{H}}_2\mathrm{O} \left(\mathrm{g}\right)$

A.  $10$

B.  $20$

C.  $40$

D.  $80$

Write the equation for the reaction of chloroethane with a dilute aqueous solution of sodium hydroxide.

Write the equation for the reaction of chloroethane with a dilute aqueous solution of sodium hydroxide.

Determine the limiting reactant, showing your calculations.

Calculate the amount, in $\mathrm{mol}$, of manganese(IV) oxide added.

Determine the limiting reactant, showing your calculations.

Determine the limiting reactant, showing your calculations.

Calculate the percentage by mass of chlorine in ${\mathrm{CCl}}_2{\mathrm{F}}_2$.

Calculate the amount, in $\mathrm{mol}$, of manganese(IV) oxide added.

Calculate the percentage by mass of chlorine in ${\mathrm{CCl}}_2{\mathrm{F}}_2$.

Calculate the percentage by mass of chlorine in ${\mathrm{CCl}}_2{\mathrm{F}}_2$.

Determine the excess amount, in $\mathrm{mol}$, of the other reactant.

Calculate the amount, in $\mathrm{mol}$, of manganese(IV) oxide added.

Determine the limiting reactant, showing your calculations.

Determine the limiting reactant, showing your calculations.

Determine the excess amount, in $\mathrm{mol}$, of the other reactant.

Determine the excess amount, in $\mathrm{mol}$, of the other reactant.

Calculate the percentage by mass of chlorine in ${\mathrm{CCl}}_2{\mathrm{F}}_2$.

Determine the limiting reactant, showing your calculations.

Determine the excess amount, in $\mathrm{mol}$, of the other reactant.

Calculate the percentage by mass of chlorine in ${\mathrm{CCl}}_2{\mathrm{F}}_2$.

Calculate the percentage by mass of chlorine in ${\mathrm{CCl}}_2{\mathrm{F}}_2$.

Write a balanced equation for the reaction.

Calculate the volume of chlorine, in ${\mathrm{dm}}^3$, produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.

Determine the excess amount, in $\mathrm{mol}$, of the other reactant.

Determine the excess amount, in $\mathrm{mol}$, of the other reactant.

Calculate the volume of chlorine, in ${\mathrm{dm}}^3$, produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.

Calculate the volume of chlorine, in ${\mathrm{dm}}^3$, produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.

Calculate the volume of chlorine, in ${\mathrm{dm}}^3$, produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.

Write a balanced equation for the reaction.

Write a balanced equation for the reaction.

Calculate the volume of chlorine, in ${\mathrm{dm}}^3$, produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.

Suggest a wavenumber absorbed by methane gas.

Comment on the magnitudes of random and systematic errors in this experiment using the answers in (e).

Calculate the volume of chlorine, in ${\mathrm{dm}}^3$, produced if the reaction is conducted at standard temperature and pressure (STP). Use section 2 of the data booklet.

Calculate the mole fraction of ethanal in the mixture.

Comment on the magnitudes of random and systematic errors in this experiment using the answers in (e).

Comment on the magnitudes of random and systematic errors in this experiment using the answers in (e).

Suggest a wavenumber absorbed by methane gas.

Suggest a wavenumber absorbed by methane gas.

Suggest a wavenumber absorbed by methane gas.

Show that the mass of the ${}_{238}\mathrm{U}$ isotope in the rock is $0.639 \mathrm{kg}$.

Calculate the mole fraction of ethanal in the mixture.

Show that the mass of the ${}_{238}\mathrm{U}$ isotope in the rock is $0.639 \mathrm{kg}$.

Show that the mass of the ${}_{238}\mathrm{U}$ isotope in the rock is $0.639 \mathrm{kg}$.

Suggest a wavenumber absorbed by methane gas.

Suggest a wavenumber absorbed by methane gas.

Calculate the mole fraction of ethanal in the mixture.

The vapour pressure of pure ethanal at $20°\mathrm{C}$ is $101 \mathrm{kPa}$.

Calculate the vapour pressure of ethanal above the liquid mixture at $20°\mathrm{C}$.

The vapour pressure of pure ethanal at $20°\mathrm{C}$ is $101 \mathrm{kPa}$.

Calculate the vapour pressure of ethanal above the liquid mixture at $20°\mathrm{C}$.

Show that the mass of the ²³⁸U isotope in the rock is $0.639 \mathrm{kg}$.

Consider the following antacids:

Show that antacid X is more effective, per tablet, than antacid Y.

The vapour pressure of pure ethanal at $20°\mathrm{C}$ is $101 \mathrm{kPa}$.

Calculate the vapour pressure of ethanal above the liquid mixture at $20°\mathrm{C}$.

Consider the following antacids:

Show that antacid X is more effective, per tablet, than antacid Y.

Show that the mass of the ²³⁸U isotope in the rock is $0.639 \mathrm{kg}$.

Show that the mass of the ²³⁸U isotope in the rock is $0.639 \mathrm{kg}$.

0.20 mol of magnesium is mixed with 0.10 mol of hydrochloric acid.

$\text{Mg\hspace{0.05em}(s)}+\text{2HCl} \text{(aq)}\to {\text{MgCl}}_{\text{2}} \text{(aq)}+{\text{H}}_{\text{2}} \text{(g)}$

Which is correct?

Write the equation for this reaction.

0.20 mol of magnesium is mixed with 0.10 mol of hydrochloric acid.

$\text{Mg\hspace{0.05em}(s)}+\text{2HCl} \text{(aq)}\to {\text{MgCl}}_{\text{2}} \text{(aq)}+{\text{H}}_{\text{2}} \text{(g)}$

Which is correct?

Write the equation for this reaction.

What volume of oxygen, in dm³ at STP, is needed when 5.8 g of butane undergoes complete combustion?

$2{\mathrm{C}}_4{\mathrm{H}}_{10} \left(\mathrm{g}\right)+13{\mathrm{O}}_2 \left(\mathrm{g}\right)\to 8{\mathrm{CO}}_2 \left(\mathrm{g}\right)+10{\mathrm{H}}_2\mathrm{O} \left(\mathrm{l}\right)$

A.  $2\times \frac{5.8}{12.01\times 4+1.01\times 10}\times 13\times 22.7$

B.  $\frac{5.8}{12.01\times 4+1.01\times 10}\times \frac{13}{2}\times 22.7$

C.  $\frac{5.8}{12.01\times 4+1.01\times 10}\times \frac{2}{13}\times 22.7$

D.  $\frac{5.8}{12.01\times 4+1.01\times 10}\times \frac{13}{2}\times \frac{22.7}{1000}$

Write the equation for this reaction.

A gaseous sample of nitrogen, contaminated only with hydrogen sulfide, was reacted with excess sodium hydroxide solution at constant temperature. The volume of the gas changed from 550 cm³ to 525 cm³.

Determine the mole percentage of hydrogen sulfide in the sample, stating one assumption you made.

What volume of oxygen, in dm³ at STP, is needed when 5.8 g of butane undergoes complete combustion?

$2{\mathrm{C}}_4{\mathrm{H}}_{10} \left(\mathrm{g}\right)+13{\mathrm{O}}_2 \left(\mathrm{g}\right)\to 8{\mathrm{CO}}_2 \left(\mathrm{g}\right)+10{\mathrm{H}}_2\mathrm{O} \left(\mathrm{l}\right)$

A.  $2\times \frac{5.8}{12.01\times 4+1.01\times 10}\times 13\times 22.7$

B.  $\frac{5.8}{12.01\times 4+1.01\times 10}\times \frac{13}{2}\times 22.7$

C.  $\frac{5.8}{12.01\times 4+1.01\times 10}\times \frac{2}{13}\times 22.7$

D.  $\frac{5.8}{12.01\times 4+1.01\times 10}\times \frac{13}{2}\times \frac{22.7}{1000}$

A gaseous sample of nitrogen, contaminated only with hydrogen sulfide, was reacted with excess sodium hydroxide solution at constant temperature. The volume of the gas changed from 550 cm³ to 525 cm³.

Determine the mole percentage of hydrogen sulfide in the sample, stating one assumption you made.

What is the coefficient of $\text{HCl}$ (aq) when the equation is balanced using the smallest possible whole numbers?

$\text{\_\_CuO\hspace{0.05em}(s)+ \_\_HCl} {\text{(aq) → \_\_CuCl}}_{\text{2}} {\text{(aq) + \_\_H}}_{\text{2}}\text{O} \text{(l)}$

A.  1

B.  2

C.  3

D.  4

What is the sum of the coefficients when the equation is balanced with whole numbers?

__Sn(OH)₄(aq) + __NaOH (aq) → __Na₂SnO₃(aq) + __H₂O (l)

A.  4

B.  5

C.  6

D.  7

A gaseous sample of nitrogen, contaminated only with hydrogen sulfide, was reacted with excess sodium hydroxide solution at constant temperature. The volume of the gas changed from 550 cm³ to 525 cm³.

Determine the mole percentage of hydrogen sulfide in the sample, stating one assumption you made.

What is the sum of the coefficients when the equation is balanced with whole numbers?

__Sn(OH)₄(aq) + __NaOH (aq) → __Na₂SnO₃(aq) + __H₂O (l)

A.  4

B.  5

C.  6

D.  7

What is the coefficient of $\text{HCl}$ (aq) when the equation is balanced using the smallest possible whole numbers?

$\text{\_\_CuO\hspace{0.05em}(s)+ \_\_HCl} {\text{(aq) → \_\_CuCl}}_{\text{2}} {\text{(aq) + \_\_H}}_{\text{2}}\text{O} \text{(l)}$

A.  1

B.  2

C.  3

D.  4

Write the equation for this reaction.

Determine the overall equation for the production of methanol.

Write the equation for this reaction.

Write the equation for this reaction.

Determine the overall equation for the production of methanol.

Determine the overall equation for the production of methanol.

Determine the overall equation for the production of methanol.

8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm³. Use sections 2 and 6 of the data booklet.

Determine the overall equation for the production of methanol.

Determine the overall equation for the production of methanol.

8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm³. Use sections 2 and 6 of the data booklet.

Calcium carbonate is heated to produce calcium oxide, CaO.

CaCO₃(s) → CaO (s) + CO₂(g)

Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.

8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm³. Use sections 2 and 6 of the data booklet.

Calcium carbonate is heated to produce calcium oxide, CaO.

CaCO₃(s) → CaO (s) + CO₂(g)

Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.

Calcium carbonate is heated to produce calcium oxide, CaO.

CaCO₃(s) → CaO (s) + CO₂(g)

Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.

8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm³. Use sections 2 and 6 of the data booklet.

8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm³. Use sections 2 and 6 of the data booklet.

8.00 g of methane is completely converted to methanol. Calculate, to three significant figures, the final volume of hydrogen at STP, in dm³. Use sections 2 and 6 of the data booklet.

What is the number of hydrogen atoms in 2.00 moles of Ca(HCO₃)₂?

Avogadro’s constant, L or N_A: 6.02 × 10²³ mol⁻¹

A.  2.00

B.  4.00

C.  1.20 × 10²⁴

D.  2.41 × 10²⁴

Calcium carbonate is heated to produce calcium oxide, CaO.

CaCO₃(s) → CaO (s) + CO₂(g)

Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.

Calcium carbonate is heated to produce calcium oxide, CaO.

CaCO₃(s) → CaO (s) + CO₂(g)

Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.

Calcium carbonate is heated to produce calcium oxide, CaO.

CaCO₃(s) → CaO (s) + CO₂(g)

Calculate the volume of carbon dioxide produced at STP when 555 g of calcium carbonate decomposes. Use sections 2 and 6 of the data booklet.

Write the equation for the reaction of Ca(OH)₂(aq) with hydrochloric acid, HCl (aq).

Write the equation for the reaction of Ca(OH)₂ (aq) with hydrochloric acid, HCl (aq).

Write the equation for the reaction of Ca(OH)₂ (aq) with hydrochloric acid, HCl (aq).

Write the equation for the reaction of Ca(OH)₂ (aq) with hydrochloric acid, HCl (aq).

What is the number of hydrogen atoms in 2.00 moles of Ca(HCO₃)₂?

Avogadro’s constant, L or N_A: 6.02 × 10²³ mol⁻¹

A.  2.00

B.  4.00

C.  1.20 × 10²⁴

D.  2.41 × 10²⁴

Determine the volume, in dm³, of 0.015 mol dm⁻³ calcium hydroxide solution needed to neutralize 35.0 cm³ of 0.025 mol dm⁻³ HCl (aq).

Determine the volume, in dm³, of 0.015 mol dm⁻³ calcium hydroxide solution needed to neutralize 35.0 cm³ of 0.025 mol dm⁻³ HCl (aq).

Determine the volume, in dm³, of 0.015 mol dm⁻³ calcium hydroxide solution needed to neutralize 35.0 cm³ of 0.025 mol dm⁻³ HCl (aq).

Write the equation for the reaction of Ca(OH)₂(aq) with hydrochloric acid, HCl (aq).

Write the equation for the reaction of Ca(OH)₂(aq) with hydrochloric acid, HCl (aq).

Determine the volume, in dm³, of 0.015 mol dm⁻³ calcium hydroxide solution needed to neutralize 35.0 cm³ of 0.025 mol dm⁻³ HCl (aq).

Determine the volume, in dm³, of 0.015 mol dm⁻³ calcium hydroxide solution needed to neutralize 35.0 cm³ of 0.025 mol dm⁻³ HCl (aq).

Determine the volume, in dm³, of 0.015 mol dm⁻³ calcium hydroxide solution needed to neutralize 35.0 cm³ of 0.025 mol dm⁻³ HCl (aq).

Determine the mass, in g, of CaCO₃(s) produced by reacting 2.41 dm³ of 2.33 × 10⁻² mol dm⁻³ of Ca(OH)₂ (aq) with 0.750 dm³ of CO₂ (g) at STP.

Determine the mass, in g, of CaCO₃(s) produced by reacting 2.41 dm³ of 2.33 × 10⁻² mol dm⁻³ of Ca(OH)₂ (aq) with 0.750 dm³ of CO₂ (g) at STP.

Determine the mass, in g, of CaCO₃(s) produced by reacting 2.41 dm³ of 2.33 × 10⁻² mol dm⁻³ of Ca(OH)₂ (aq) with 0.750 dm³ of CO₂ (g) at STP.

2.85 g of CaCO₃ was collected in the experiment in d(i). Calculate the percentage yield of CaCO₃.

(If you did not obtain an answer to d(i), use 4.00 g, but this is not the correct value.)

2.85 g of CaCO₃ was collected in the experiment in d(i). Calculate the percentage yield of CaCO₃.

(If you did not obtain an answer to d(i), use 4.00 g, but this is not the correct value.)

2.85 g of CaCO₃ was collected in the experiment in d(i). Calculate the percentage yield of CaCO₃.

(If you did not obtain an answer to d(i), use 4.00 g, but this is not the correct value.)

Determine the mass, in g, of CaCO₃(s) produced by reacting 2.41 dm³ of 2.33 × 10⁻² mol dm⁻³ of Ca(OH)₂ (aq) with 0.750 dm³ of CO₂ (g) at STP.

Determine the mass, in g, of CaCO₃(s) produced by reacting 2.41 dm³ of 2.33 × 10⁻² mol dm⁻³ of Ca(OH)₂ (aq) with 0.750 dm³ of CO₂ (g) at STP.

Determine the mass, in g, of CaCO₃(s) produced by reacting 2.41 dm³ of 2.33 × 10⁻² mol dm⁻³ of Ca(OH)₂ (aq) with 0.750 dm³ of CO₂ (g) at STP.

2.85 g of CaCO₃ was collected in the experiment in e(i). Calculate the percentage yield of CaCO₃.

(If you did not obtain an answer to e(i), use 4.00 g, but this is not the correct value.)

2.85 g of CaCO₃ was collected in the experiment in e(i). Calculate the percentage yield of CaCO₃.

(If you did not obtain an answer to e(i), use 4.00 g, but this is not the correct value.)

2.85 g of CaCO₃ was collected in the experiment in e(i). Calculate the percentage yield of CaCO₃.

(If you did not obtain an answer to e(i), use 4.00 g, but this is not the correct value.)

Write the chemical equation for the complete combustion of ethanol.

Write the chemical equation for the complete combustion of ethanol.

Write the chemical equation for the complete combustion of ethanol.

Determine the empirical formula of the compound using section 6 of the data booklet.

3.00 mol of C₃H₈ is mixed with 20.00 mol of O₂. Which quantity is present at the end of the reaction?

C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O (g)

A.  1.00 mol of C₃H₈

B.  5.00 mol of O₂

C.  12.00 mol of CO₂

D.  16.00 mol of H₂O

Determine the empirical formula of the compound using section 6 of the data booklet.

Determine the empirical formula of the compound using section 6 of the data booklet.

Determine the molecular formula of this compound if its molar mass is 88.12 g mol⁻¹. If you did not obtain an answer in (a) use CS, but this is not the correct answer.

Formulate an equation for the reaction of one mole of phosphoric acid with one mole of sodium hydroxide.

3.00 mol of C₃H₈ is mixed with 20.00 mol of O₂. Which quantity is present at the end of the reaction?

C₃H₈(g) + 5O₂(g) → 3CO₂(g) + 4H₂O (g)

A.  1.00 mol of C₃H₈

B.  5.00 mol of O₂

C.  12.00 mol of CO₂

D.  16.00 mol of H₂O

Write an equation for the reaction of white phosphorus (P₄) with chlorine gas to form phosphorus trichloride (PCl₃).

Determine the molecular formula of this compound if its molar mass is 88.12 g mol⁻¹. If you did not obtain an answer in (a) use CS, but this is not the correct answer.

Determine the molecular formula of this compound if its molar mass is 88.12 g mol⁻¹. If you did not obtain an answer in (a) use CS, but this is not the correct answer.

Write an equation for the reaction of white phosphorus (P₄) with chlorine gas to form phosphorus trichloride (PCl₃).

Formulate an equation for the reaction of one mole of phosphoric acid with one mole of sodium hydroxide.

Formulate an equation for the reaction of one mole of phosphoric acid with one mole of sodium hydroxide.

Calculate the concentration of H₃PO₄ if 25.00 cm³ is completely neutralised by the addition of 28.40 cm³ of 0.5000 mol dm⁻³ NaOH.

Write an equation for the reaction of white phosphorus (P₄) with chlorine gas to form phosphorus trichloride (PCl₃).

Calculate the concentration of H₃PO₄ if 25.00 cm³ is completely neutralised by the addition of 28.40 cm³ of 0.5000 mol dm⁻³ NaOH.

Calculate the concentration of H₃PO₄ if 25.00 cm³ is completely neutralised by the addition of 28.40 cm³ of 0.5000 mol dm⁻³ NaOH.

Write an equation for the reaction of white phosphorus (P₄) with chlorine gas to form phosphorus trichloride (PCl₃).

Write an equation for the reaction of white phosphorus (P₄) with chlorine gas to form phosphorus trichloride (PCl₃).

Write an equation for the reaction of white phosphorus (P₄) with chlorine gas to form phosphorus trichloride (PCl₃).

0.2 mol of sodium hydrogencarbonate is decomposed by heating until constant mass.

2 NaHCO₃(s) → Na₂CO₃ (s) + H₂O (g) + CO₂ (g)

How many moles of gas are produced?

A.  0.1

B.  0.2

C.  0.3

D.  0.4

Formulate an equation for the reaction of one mole of phosphoric acid with one mole of sodium hydroxide.

Formulate an equation for the reaction of one mole of phosphoric acid with one mole of sodium hydroxide.

Formulate an equation for the reaction of one mole of phosphoric acid with one mole of sodium hydroxide.

Calculate the concentration of H₃PO₄ if 25.00 cm³ is completely neutralised by the addition of 28.40 cm³ of 0.5000 mol dm⁻³ NaOH.

Calculate the concentration of H₃PO₄ if 25.00 cm³ is completely neutralised by the addition of 28.40 cm³ of 0.5000 mol dm⁻³ NaOH.

Calculate the concentration of H₃PO₄ if 25.00 cm³ is completely neutralised by the addition of 28.40 cm³ of 0.5000 mol dm⁻³ NaOH.

Calculate the amount, in moles of Na₂S₂O₃ used in the titration.

Calculate the amount, in moles of Na₂S₂O₃ used in the titration.

Calculate the amount, in moles of Na₂S₂O₃ used in the titration.

Calculate the concentration of dissolved oxygen, in mol dm⁻³, in the sample.

Calculate the concentration of dissolved oxygen, in mol dm⁻³, in the sample.

Calculate the concentration of dissolved oxygen, in mol dm⁻³, in the sample.

2.67 g of lead (II) carbonate is decomposed by heating until constant mass.

PbCO₃(s) → PbO (s) + CO₂(g)

What is the final mass of solid?

A.  0.44 g

B.  2.23 g

C.  2.67 g

D.  3.11 g

Calculate the amount, in moles of Na₂S₂O₃ used in the titration.

Calculate the amount, in moles of Na₂S₂O₃ used in the titration.

Calculate the amount, in moles of Na₂S₂O₃ used in the titration.

Calculate the concentration of dissolved oxygen, in mol dm⁻³, in the sample.

Calculate the concentration of dissolved oxygen, in mol dm⁻³, in the sample.

Calculate the concentration of dissolved oxygen, in mol dm⁻³, in the sample.

Determine the empirical formula of the compound using section 6 of the data booklet.

Determine the empirical formula of the compound using section 6 of the data booklet.

Determine the empirical formula of the compound using section 6 of the data booklet.

Determine the molecular formula of this compound if its molar mass is 88.12 g mol⁻¹. If you did not obtain an answer in (a) use CS, but this is not the correct answer.

Determine the molecular formula of this compound if its molar mass is 88.12 g mol⁻¹. If you did not obtain an answer in (a) use CS, but this is not the correct answer.

Determine the molecular formula of this compound if its molar mass is 88.12 g mol⁻¹. If you did not obtain an answer in (a) use CS, but this is not the correct answer.

0.2 mol of sodium hydrogencarbonate is decomposed by heating until constant mass.

2 NaHCO₃(s) → Na₂CO₃ (s) + H₂O (g) + CO₂ (g)

How many moles of gas are produced?

A.  0.1

B.  0.2

C.  0.3

D.  0.4

2.67 g of lead (II) carbonate is decomposed by heating until constant mass.

PbCO₃(s) → PbO (s) + CO₂(g)

What is the final mass of solid?

A.  0.44 g

B.  2.23 g

C.  2.67 g

D.  3.11 g

0.02 mol of zinc is added to 10.0 cm³ of 1.0 mol dm^–3 hydrochloric acid.

Zn (s) + 2HCl (aq) → ZnCl₂(aq) + H₂(g)

How many moles of hydrogen are produced?

A.  0.005

B.  0.01

C.  0.02

D.  0.04

Which sample contains the fewest moles of HCl?

N_A = 6.02 × 10²³mol^–1.

Molar volume of an ideal gas at STP = 22.7 dm³mol^–1.

A.  10.0 cm³ of 0.1 mol dm^–3 HCl (aq)

B.  6.02 × 10²⁴ molecules of HCl (g)

C.  0.365 g of HCl (g)

D.  2.27 dm³ of HCl (g) at STP

0.02 mol of zinc is added to 10.0 cm³ of 1.0 mol dm^–3 hydrochloric acid.

Zn (s) + 2HCl (aq) → ZnCl₂(aq) + H₂(g)

How many moles of hydrogen are produced?

A.  0.005

B.  0.01

C.  0.02

D.  0.04

Which sample contains the fewest moles of HCl?

N_A = 6.02 × 10²³mol^–1.

Molar volume of an ideal gas at STP = 22.7 dm³mol^–1.

A.  10.0 cm³ of 0.1 mol dm^–3 HCl (aq)

B.  6.02 × 10²⁴ molecules of HCl (g)

C.  0.365 g of HCl (g)

D.  2.27 dm³ of HCl (g) at STP

Write a balanced equation for the reaction that occurs.

Which equation represents the deposition of iodine?

A.  I₂(g) → I₂(l)

B.  I₂(g) → I₂(s)

C.  I₂(l) → I₂(g)

D.  I₂(s) → I₂(g)

Which equation represents the deposition of iodine?

A.  I₂(g) → I₂(l)

B.  I₂(g) → I₂(s)

C.  I₂(l) → I₂(g)

D.  I₂(s) → I₂(g)

Write a balanced equation for the reaction that occurs.

Write a balanced equation for the reaction that occurs.

Determine the coefficients that balance the equation for the reaction of lithium with water.

Calculate the amount of magnesium, in mol, that was used.

Calculate the amount of magnesium, in mol, that was used.

Calculate the amount of magnesium, in mol, that was used.

Determine the concentration, in mol dm^–3, of the solution formed when 900.0 dm³ of NH₃(g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm³ of solution. Use sections 1 and 2 of the data booklet.

Determine the concentration, in mol dm^–3, of the solution formed when 900.0 dm³ of NH₃(g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm³ of solution. Use sections 1 and 2 of the data booklet.

Determine the concentration, in mol dm^–3, of the solution formed when 900.0 dm³ of NH₃(g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm³ of solution. Use sections 1 and 2 of the data booklet.

Determine the coefficients that balance the equation for the reaction of lithium with water.

Write a balanced equation for the reaction that occurs.

Determine the coefficients that balance the equation for the reaction of lithium with water.

Calculate the molar concentration of the resulting solution of lithium hydroxide.

Write a balanced equation for the reaction that occurs.

Write a balanced equation for the reaction that occurs.

Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.

Calculate the molar concentration of the resulting solution of lithium hydroxide.

Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.

Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.

Calculate the amount of magnesium, in mol, that was used.

Calculate the molar concentration of the resulting solution of lithium hydroxide.

Calculate the volume of hydrogen gas produced, in cm³, if the temperature was 22.5 °C and the pressure was 103 kPa. Use sections 1 and 2 of the data booklet.

Calculate the amount of magnesium, in mol, that was used.

Calculate the amount of magnesium, in mol, that was used.

Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).

Calculate the volume of hydrogen gas produced, in cm³, if the temperature was 22.5 °C and the pressure was 103 kPa. Use sections 1 and 2 of the data booklet.

Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.

Calculate the volume of hydrogen gas produced, in cm³, if the temperature was 22.5 °C and the pressure was 103 kPa. Use sections 1 and 2 of the data booklet.

How many oxygen atoms are present in 0.0500 mol Ba(OH)₂•8H₂O?

N_A = 6.02 × 10²³

A.   3.01 × 10²³

B.   6.02 × 10²³

C.   3.01 × 10²⁴

D.   6.02 × 10²⁴

Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.

Assume the reaction in (a)(i) is the only one occurring and it goes to completion, but some product has been lost from the crucible. Deduce the percentage yield of magnesium oxide in the crucible.

Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).

Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).

Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).

Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).

Evaluate whether this, rather than the loss of product, could explain the yield found in (b)(iii).

Calculate coefficients that balance the equation for the following reaction.

__ Mg₃N₂(s) + __ H₂O (l) → __ Mg(OH)₂(s) + __ NH₃(aq)

How many oxygen atoms are present in 0.0500 mol Ba(OH)₂•8H₂O?

N_A = 6.02 × 10²³

A.   3.01 × 10²³

B.   6.02 × 10²³

C.   3.01 × 10²⁴

D.   6.02 × 10²⁴

Calculate coefficients that balance the equation for the following reaction.

__ Mg₃N₂(s) + __ H₂O (l) → __ Mg(OH)₂(s) + __ NH₃(aq)

Calculate coefficients that balance the equation for the following reaction.

__ Mg₃N₂(s) + __ H₂O (l) → __ Mg(OH)₂(s) + __ NH₃(aq)

What is the coefficient for H⁺ when the equation below is balanced?

__Pb (s) + __NO₃⁻ (aq) + __H⁺ (aq) → __Pb²⁺ (aq) + __NO (g) + __H₂O (l)

A.  2

B.  4

C.  6

D.  8

Calculate coefficients that balance the equation for the following reaction.

Calculate coefficients that balance the equation for the following reaction.

Calculate coefficients that balance the equation for the following reaction.

Determine the concentration, in mol dm^–3, of the solution formed when 900.0 dm³ of NH₃(g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm³ of solution. Use sections 1 and 2 of the data booklet.

Determine the concentration, in mol dm^–3, of the solution formed when 900.0 dm³ of NH₃(g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm³ of solution. Use sections 1 and 2 of the data booklet.

Determine the concentration, in mol dm^–3, of the solution formed when 900.0 dm³ of NH₃(g) at 300.0 K and 100.0 kPa, is dissolved in water to form 2.00 dm³ of solution. Use sections 1 and 2 of the data booklet.

What is the coefficient for H⁺ when the equation below is balanced?

__Pb (s) + __NO₃⁻ (aq) + __H⁺ (aq) → __Pb²⁺ (aq) + __NO (g) + __H₂O (l)

A.  2

B.  4

C.  6

D.  8

Calculate the percentage by mass of nitrogen in ammonium nitrate. Use section 6 of the data booklet.

Calculate the percentage by mass of nitrogen in ammonium nitrate. Use section 6 of the data booklet.

Calculate the percentage by mass of nitrogen in ammonium nitrate. Use section 6 of the data booklet.

Write the chemical equation for this decomposition.

Write the chemical equation for this decomposition.

Write the chemical equation for this decomposition.

How many moles of carbon dioxide are produced by the complete combustion of 7.0 g of ethene, C₂H₄ (g)?

M_r = 28

A.  0.25

B.  0.5

C.  0.75

D.  1.0

Calculate the volume of dinitrogen monoxide produced at STP when a 5.00 g sample of ammonium nitrate decomposes. Use section 2 of the data booklet.

Write the chemical equation for this decomposition.

How many moles of carbon dioxide are produced by the complete combustion of 7.0 g of ethene, C₂H₄ (g)?

M_r = 28

A.  0.25

B.  0.5

C.  0.75

D.  1.0

Write the chemical equation for this decomposition.

Write the chemical equation for this decomposition.

Calculate the volume of dinitrogen monoxide produced at STP when a 5.00 g sample of ammonium nitrate decomposes. Use section 2 of the data booklet.

Calculate the volume of dinitrogen monoxide produced at STP when a 5.00 g sample of ammonium nitrate decomposes. Use section 2 of the data booklet.

Which is a possible empirical formula for a substance with M_r = 42?

A.  CH

B.  CH₂

C.  C₃H₆

D.  C₃H₈

Calculate the volume of dinitrogen monoxide produced at STP when a 5.00 g sample of ammonium nitrate decomposes. Use section 2 of the data booklet.

Which is a possible empirical formula for a substance with M_r = 42?

A.  CH

B.  CH₂

C.  C₃H₆

D.  C₃H₈

Calculate the volume of dinitrogen monoxide produced at STP when a 5.00 g sample of ammonium nitrate decomposes. Use section 2 of the data booklet.

Calculate the volume of dinitrogen monoxide produced at STP when a 5.00 g sample of ammonium nitrate decomposes. Use section 2 of the data booklet.

Calculate the amount, in mol, of sulfur dioxide produced when 500.0 g of lignite undergoes combustion.

S (s) + O₂ (g) → SO₂ (g)

Calculate the amount, in mol, of sulfur dioxide produced when 500.0 g of lignite undergoes combustion.

S (s) + O₂ (g) → SO₂ (g)

Calculate the amount, in mol, of sulfur dioxide produced when 500.0 g of lignite undergoes combustion.

S (s) + O₂ (g) → SO₂ (g)

Calculate the amount, in mol, of sulfur dioxide produced when 500.0 g of lignite undergoes combustion.

S (s) + O₂ (g) → SO₂ (g)

Calculate the percentage by mass of nitrogen in ammonium nitrate. Use section 6 of the data booklet.

Calculate the percentage by mass of nitrogen in ammonium nitrate. Use section 6 of the data booklet.

Calculate the percentage by mass of nitrogen in ammonium nitrate. Use section 6 of the data booklet.

Ammonium nitrate is neutralized with sodium hydroxide. Write the equation for the reaction.

Ammonium nitrate is neutralized with sodium hydroxide. Write the equation for the reaction.

Ammonium nitrate is neutralized with sodium hydroxide. Write the equation for the reaction.

Deduce the ionic equation, including state symbols, for the reaction of hydrogen chloride gas with water.

Deduce the ionic equation, including state symbols, for the reaction of hydrogen chloride gas with water.

Deduce the ionic equation, including state symbols, for the reaction of hydrogen chloride gas with water.

Calculate the amount, in mol, of sulfur dioxide produced when 500.0 g of lignite undergoes combustion.

S (s) + O₂ (g) → SO₂ (g)

Calculate the amount, in mol, of sulfur dioxide produced when 500.0 g of lignite undergoes combustion.

S (s) + O₂ (g) → SO₂ (g)

Draw one Lewis (electron dot) structure of the sulfate ion.

Draw one Lewis (electron dot) structure of the sulfate ion.

Draw one Lewis (electron dot) structure of the sulfate ion.

Calculate the percentage of oxygen present in the double salt.

Calculate the percentage of oxygen present in the double salt.

Calculate the percentage of oxygen present in the double salt.

Calculate the percentage of oxygen present in the double salt.

Calculate the percentage of oxygen present in the double salt.

Calculate the percentage of oxygen present in the double salt.

A series of experiments were carried out at different temperatures and the rate of reaction, in mol dm⁻³s⁻¹, was determined for each. The rate constant for the reaction of propanone (CH₃COCH₃) with iodine (I₂) was calculated and the processed data is represented in the following graph.

Determine the activation energy for this reaction, stating the units. Use sections 1 and 2 of the data booklet.

A series of experiments were carried out at different temperatures and the rate of reaction, in mol dm⁻³s⁻¹, was determined for each. The rate constant for the reaction of propanone (CH₃COCH₃) with iodine (I₂) was calculated and the processed data is represented in the following graph.

Determine the activation energy for this reaction, stating the units. Use sections 1 and 2 of the data booklet.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

The concentration of methanoic acid was found by titration with a 0.200 mol dm⁻³ standard solution of sodium hydroxide, NaOH (aq), using an indicator to determine the end point.

What is the molar mass of a gas according to the following experimental data?

Ideal gas constant = 8.31 J K⁻¹ mol⁻¹
PV = nRT

A.  $\frac{40.0\times 8.31\times 290}{98\times 0.220}$

B.  $\frac{98\times 0.220}{40.0\times 8.31\times 290}$

C.  $\frac{40.0\times 8.31\times 17}{98\times 0.220}$

D.  $\frac{98\times 0.220}{40.0\times 8.31\times 17}$

What is the molar mass of a gas according to the following experimental data?

Ideal gas constant = 8.31 J K⁻¹ mol⁻¹
PV = nRT

A.  $\frac{40.0\times 8.31\times 290}{98\times 0.220}$

B.  $\frac{98\times 0.220}{40.0\times 8.31\times 290}$

C.  $\frac{40.0\times 8.31\times 17}{98\times 0.220}$

D.  $\frac{98\times 0.220}{40.0\times 8.31\times 17}$

What is the molar mass of a gas according to the following experimental data?

Ideal gas constant = 8.31 J K⁻¹ mol⁻¹
PV = nRT

A.  $\frac{40.0\times 8.31\times 290}{98\times 0.220}$

B.  $\frac{98\times 0.220}{40.0\times 8.31\times 290}$

C.  $\frac{40.0\times 8.31\times 17}{98\times 0.220}$

D.  $\frac{98\times 0.220}{40.0\times 8.31\times 17}$

What is the molar mass of a gas according to the following experimental data?

Ideal gas constant = 8.31 J K⁻¹ mol⁻¹
PV = nRT

A.  $\frac{40.0\times 8.31\times 290}{98\times 0.220}$

B.  $\frac{98\times 0.220}{40.0\times 8.31\times 290}$

C.  $\frac{40.0\times 8.31\times 17}{98\times 0.220}$

D.  $\frac{98\times 0.220}{40.0\times 8.31\times 17}$

In the following unbalanced equation, X represents an element.

Which oxide reacts with water as shown?

____ + H₂O → X(OH)₂

A.  Na₂O

B.  MgO

C.  NO₂

D.  SO₃

In the following unbalanced equation, X represents an element.

Which oxide reacts with water as shown?

____ + H₂O → X(OH)₂

A.  Na₂O

B.  MgO

C.  NO₂

D.  SO₃

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

20 cm³ of gas A reacts with 20 cm³ of gas B to produce 10 cm³ of gas A_xB_y and 10 cm³ of excess gas A. What are the correct values for subscripts x and y in the empirical formula of the product A_xB_y (g)?

An unknown organic compound, X, comprising of only carbon, hydrogen and oxygen was found to contain 48.6 % of carbon and 43.2 % of oxygen.

Determine the empirical formula.

An unknown organic compound, X, comprising of only carbon, hydrogen and oxygen was found to contain 48.6 % of carbon and 43.2 % of oxygen.

Determine the empirical formula.

An unknown organic compound, X, comprising of only carbon, hydrogen and oxygen was found to contain 48.6 % of carbon and 43.2 % of oxygen.

Determine the empirical formula.

Which are the correct sequences of increasing bond strengths and bond lengths between two carbon atoms?

Which are the correct sequences of increasing bond strengths and bond lengths between two carbon atoms?

Which condition will cause the given equilibrium to shift to the right?

Ag⁺ (aq) + Cl⁻ (aq) ⇌ AgCl (s)

A.  One half of solid AgCl is removed.

B.  Water is added.

C.  Solid NaCl is added.

D.  The system is subjected to increased pressure.

Which condition will cause the given equilibrium to shift to the right?

Ag⁺ (aq) + Cl⁻ (aq) ⇌ AgCl (s)

A.  One half of solid AgCl is removed.

B.  Water is added.

C.  Solid NaCl is added.

D.  The system is subjected to increased pressure.