Preliminary organic chemistry tutorial 2

Organic chemistry Multiple choice questions and answers

1.With which one of the following reagents does propanone undergo a different type of reaction from ethanol

(a)HCN

(b)NaHSO3

(c)NH3

(d)NH2NH2

(e)NH2OH

2.Which of the following compounds does not give a positive result with the iodoform test?

(a)CH3CHO

(b) CH3Ch2OH

(c)CCl3COCH3

(d)CH3Ch2CH2OHCH3

(e)C5H5CH2CH2OH

3.Ethanol and propanone react differently with which of these reagents?

(a)phenylhydrazine

(b)Bradys reagent

(c)semicarbazide
(d)Fehlings solution

(e)Schiff bases

4.Which of the following reagents is used to distinguish between ketones and aldehydes?

(a)2,4-dinitrophenylhydrazine (2,4-DNPH)

(b) PCl5 in dry conditions

(c) NaHCO3(aq)

(d)Tollens reagent

5Which of the following does not react with methyl benzene?

(a) concentrated sulphuric acid

(b)chlorine gas

(c)bromine water

(d) Acidified potassium manganate(VII)

(e) acetic anhydride

6.Which of the following reagents does not undergo reaction with ethene?

(a)acidified potassium manganate(VII)

(b)hydrgen cyanide

(c) aqueous ammonia

(d)bromine in tetrachloromethane

(e)hydrogen chloride

7.Ethoxyethane (bp 308K) is more volatile than ethanol (bp 351K) largely because of:

(a)the greater relative molecular mass of the ether

(b)the strength of th C-O bonds in the ether

(c)the different shapes of molecules

(d)the highly polar-OH group in ethanol

(e) intramolecular hydrogen bonding between ether molecules

8. Which of the following is the strongest acid?

(a)benzenecarboxylic acid

(b)trichloroethanoic acid

(c)carbonic acid

(d)sodium hydrogensulphate

9.Which of the following compounds is a polyester

(a)dimethyl benzene-1,4-dicarboxylate

(b)poly(ethenyl ethanoate)

(c) Nylon 6,6

(d) terylene

(e)poly(phenylethene)(polystyrene)

10.Which of the following is an inaccurate description of a nucleophile

(a) an acidic reagent

(b)a basic reagent

(c) an electron-rich species

(d) a species which often contains a lone pair of electrons

(e) a reagent which attacks electron deficient sites in molecules

Answers:

1C 2E 3D 4D 5C 6C 7D 8B 9 D 10A