CAIE A-Level Chemistry AS 13.1 Formulas Functional Groups and Nomenclature Questions

Practise recognising functional groups, switching between organic formula styles and applying systematic names.

Exam points

identify the functional group that controls the characteristic reactions of an organic compound
translate among molecular, structural, displayed and skeletal formulae without changing connectivity
choose the principal functional group, number the carbon chain and construct a systematic name

Covered syllabus points

13.1.1—Terms: hydrocarbon as a compound made up of C 13.1.2—Alkanes are simple hydrocarbons with no 13.1.3—Compounds in the table on pages 29 and 30 13.1.4—Interpret/use the general, structural,13.1.5—Systematic nomenclature of simple aliphatic 13.1.6—The molecular and/or empirical formula

[Maximum number: 1]

Two hydrocarbons have the formulae $\mathrm{C}_{\mathrm{W}} \mathrm{H}_{\mathrm{X}}$ and $\mathrm{C}_{\mathrm{Y}} \mathrm{H}_{\mathrm{Z}}$ . W, X, Y and Z represent different whole numbers.

\frac{W}{X}=\frac{Y}{Z}

Which row is correct when comparing the two hydrocarbons?

empirical formula

molecular formula

relative molecular mass

different

same

different

same

different

same

different

same

[Maximum number: 1]

The formulae of three compounds are shown.

\mathrm{C}_{3} \mathrm{H}_{7} \mathrm{CHO} \quad \mathrm{C}_{2} \mathrm{H}_{5} \mathrm{COCH}_{3} \quad \mathrm{CH}_{2} \mathrm{CHCH}_{2} \mathrm{CH}_{2} \mathrm{OH}

Only one of these compounds will decolourise bromine water. Only one of these compounds will produce a silver mirror with Tollens' reagent.

Which row shows the correct results?

decolourises bromine water

forms a silver mirror with Tollens' reagent

$\mathrm{C}_{3} \mathrm{H}_{7} \mathrm{CHO}$

$\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{COCH}_{3}$

$\mathrm{C}_{3} \mathrm{H}_{7} \mathrm{CHO}$

$\mathrm{CH}_{2} \mathrm{CHCH}_{2} \mathrm{CH}_{2} \mathrm{OH}$

$\mathrm{C}_{2} \mathrm{H}_{5} \mathrm{COCH}_{3}$

$\mathrm{CH}_{2} \mathrm{CHCH}_{2} \mathrm{CH}_{2} \mathrm{OH}$

$\mathrm{C}_{3} \mathrm{H}_{7} \mathrm{CHO}$

[Maximum number: 1]

In the general formula of which class of compound is the ratio of hydrogen atoms to carbon atoms the highest?

alcohols

aldehydes

carboxylic acids

halogenoalkanes

[Maximum number: 1]

An ester X has the structural formula $\mathrm{CH}_{3} \mathrm{CO}_{2} \mathrm{CH}\left(\mathrm{CH}_{3}\right) \mathrm{CH}_{2} \mathrm{CH}_{3}$ . X can be prepared by heating an alcohol Y, under reflux, with ethanoic acid and an acid catalyst.

What is the correct name for Y ?

butan-1-ol

butan-2-ol

butan-3-ol

methylpropan-2-ol

[Maximum number: 1]

The diagram shows the skeletal formula of citric acid.

citric acid

What is the molecular formula of citric acid?

$\mathrm{C}_{6} \mathrm{H}_{8} \mathrm{O}_{7}$

$\mathrm{C}_{6} \mathrm{H}_{4} \mathrm{O}_{7}$

$\mathrm{C}_{8} \mathrm{H}_{8} \mathrm{O}_{7}$

$\mathrm{C}_{10} \mathrm{H}_{8} \mathrm{O}_{7}$

All question bank results loaded

Covered syllabus points

Question 1

Question 2

Question 3

Question 4

Question 5