1.2 The mole concept

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

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

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

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.

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).

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

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

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.

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

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.

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

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

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

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

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

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

Determine the limiting reactant showing your working.

Determine the limiting reactant showing your working.

Determine the limiting reactant showing your working.

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.

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

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.

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.

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.

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.

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.

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.

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

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.

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

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

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

A.  CH

B.  CH₂

C.  C₃H₆

D.  C₃H₈

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

A.  CH

B.  CH₂

C.  C₃H₆

D.  C₃H₈

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.

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

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

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

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

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 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.

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.

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 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 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 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.

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

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.

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.

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

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

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

Determine the limiting reactant showing your working.

Determine the limiting reactant showing your working.

Determine the limiting reactant showing your working.

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

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

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

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.

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.

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

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.

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.

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:

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.

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

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

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

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 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.  $2.4\times {10}^{23}$

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

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

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

Consider the following antacids:

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

Consider the following antacids:

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

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.

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.

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

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

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

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.

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

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 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.

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

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.

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.

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.