DP Chemistry (last assessment 2024)

Test builder »

Question 18N.2.sl.TZ0.2

Select a Test
Date November 2018 Marks available [Maximum mark: 7] Reference code 18N.2.sl.TZ0.2
Level sl Paper 2 Time zone TZ0
Command term Calculate, Classify, Deduce, Draw, State Question number 2 Adapted from N/A
2.
[Maximum mark: 7]
18N.2.sl.TZ0.2

Propan-2-ol is a useful organic solvent.

(a)

Draw the structural formula of propan-2-ol.

[1]

Markscheme

CH3CH(OH)CH3

 

Accept the full or condensed structural formula.

(b)

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

[2]

Markscheme

« 1.00 g ( 12.01 × 3 + 1.01 × 8 + 16.00 ) g mo l − 1 = »  0.0166  «mol CH3CH(OH)CH3» ✔

«0.0166 mol × 6.02 × 1023 molecules mol−1 × 8 atoms molecule−1 =» 8.01 × 1022 «atoms of hydrogen» ✔ 

 

Accept answers in the range 7.99 × 1022 to 8.19 × 1022.

Award [2] for correct final answer.

(c)

Classify propan-2-ol as a primary, secondary or tertiary alcohol, giving a reason.

[1]

Markscheme

secondary AND OH/hydroxyl is attached to a carbon bonded to one hydrogen

OR

secondary AND OH/hydroxyl is attached to a carbon bonded to two C/R/alkyl/CH3 «groups» ✔

 

Accept “secondary AND OH is attached to the second carbon in the chain”.

(d.i)

State a suitable oxidizing agent for the oxidation of propan-2-ol in an acidified aqueous solution.

[1]

Markscheme

«potassium/sodium» manganate(VII)/permanganate/KMnO4/NaMnO4/MnO4−

OR

«potassium/sodium» dichromate(VI)/K2Cr2O7/Na2Cr2O7/Cr2O72− ✔

(d.ii)

Deduce the average oxidation state of carbon in propan-2-ol.

[1]

Markscheme

−2 ✔

(d.iii)

Deduce the product of the oxidation of propan-2-ol with the oxidizing agent in (d)(i).

[1]

Markscheme

propanone/propan-2-one/CH3COCH3 ✔

Syllabus sections