(a)

(i)

Describe two observations you would make during the reaction when ethanedioic acid, $\mathrm{H}_{2} \mathrm{C}_{2} \mathrm{O}_{4}$ , is warmed with acidified manganate(VII) ions.

[ 2 ]

[Maximum number: 1]

Which row is correct?

shape of $\mathrm{H}_{3} \mathrm{O}^{+}$

shape of $\mathrm{SCl}_{2}$

pyramidal

non-linear

pyramidal

linear

trigonal planar

non-linear

trigonal planar

linear

(a)

Fehling's reagent is an alkaline solution of $\mathrm{Cu}^{2+}$ ions complexed with tartrate ions. It is used in organic chemistry to test for a particular functional group.

[ 3 ]

(i)

Name the functional group involved.

(ii)

Describe the appearance of a positive result in this test.

(iii)

Write an equation for the reaction between $\mathrm{Cu}^{2+}$ and $\mathrm{OH}^{-}$ ions and a two-carbon compound containing the functional group you named in (i).

[ 3 ]

[Maximum number: 1]

Which reagent gives the same visible result with propanal and with propan-2-ol?

A

2,4-dinitrophenylhydrazine reagent

B

acidified potassium dichromate(VI)

C

sodium

D

Tollens' reagent

[Maximum number: 1]

A carbonyl compound X will react with HCN in the presence of NaCN to make a compound with $M_{\mathrm{r}} 85$ . Compound X does not react with Fehling's reagent.

What is X ?

A

butanal

B

butanone

C

propanal

D

propanone

[Maximum number: 1]

Acrylic acid is produced from propene, a gaseous product of oil refineries.

acrylic acid

Which statement about acrylic acid is not correct?

A

Both bond angles x and y are approximately $120^{\circ}$ .

B

It decolourises aqueous bromine.

C

It gives an orange precipitate with 2,4-dinitrophenylhydrazine reagent.

D

It reacts with an alcohol to give an ester.

[Maximum number: 5]

Over one million tonnes of hydrogen cyanide, HCN , are produced each year using the Andrussow process. The overall equation for the reaction is shown.

\mathrm{CH}_{4}(\mathrm{~g})+\mathrm{NH}_{3}(\mathrm{~g})+1 \frac{1}{2} \mathrm{O}_{2}(\mathrm{~g}) \rightleftharpoons \mathrm{HCN}(\mathrm{~g})+3 \mathrm{H}_{2} \mathrm{O}(\mathrm{~g})

(a)

The reaction of hydrogen cyanide with propanone is an important first step in many organic syntheses.

[ 5 ]

(i)

Complete the diagram to show the mechanism of the reaction of hydrogen cyanide with propanone.
Draw the structure of the intermediate and the product of the reaction. Include all relevant charges, partial charges, curly arrows and lone pairs.

[ 5 ]

[Maximum number: 1]

Aldehydes and ketones are carbonyl compounds.
Which of them react with both $\mathrm{LiAlH}_{4}$ and Tollens' reagent?

A

aldehydes only

B

both aldehydes and ketones

C

ketones only

D

neither aldehydes nor ketones

[Maximum number: 1]

Methanoic acid, $\mathrm{HCO}_{2} \mathrm{H}$ , has acidic properties similar to those of other carboxylic acids. In addition it can be oxidised by the same oxidising agents that are capable of oxidising aldehydes.

Which pair consists of two compounds that will give the same observations with Fehling's reagent?

A

$\mathrm{HCO}_{2} \mathrm{H}$ and $\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{H}$

B

$\mathrm{HCO}_{2} \mathrm{H}$ and $\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{CH}_{3}$

C

$\mathrm{HCO}_{2} \mathrm{H}$ and $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{COCH}_{3}$

D

$\mathrm{HCO}_{2} \mathrm{H}$ and $\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CHO}$

[Maximum number: 1]

When ethanal, $\mathrm{CH}_{3} \mathrm{CHO}$ , reacts with HCN and the organic product is hydrolysed by aqueous acid, organic compound Y is formed.

When propanal, $\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{CHO}$ , is heated under reflux with acidified potassium dichromate(VI), organic compound Z is formed.

What is the difference in relative molecular mass of compounds Y and Z ?

A

12

B

14

C

16

D

17

Question 1

Question 1(d)

Question 1(d)(ii)

Question 6

Question 3

Question 3(e)

Question 3(e)(i)

Question 3(e)(ii)

Question 3(e)(iii)

Question 20

Question 20

Question 21

Question 3

Question 3(d)

Question 3(d)(ii)

Question 21

Question 22

Question 22