chemistry MCQs - 12th class Chapter 11 Mcqs

1

Alcohols, phenols, and ethers are considered derivatives of which compound?

A

Alkanes

B

Benzene

C

Water

D

Carbonic acid

2

Which of the following is a tertiary alcohol?

A

CH3-CH2-OH

B

CH3-CH(OH)-CH3

C

(CH3)3C-OH

D

C6H5CH2OH

3

The common name for Methanol is?

A

Grain spirit

B

Wood spirit

C

Rubbing alcohol

D

Carbolic acid

4

In the IUPAC system, the ending 'e' of an alkane is replaced by what for an alcohol?

A

al

B

one

C

oic acid

D

ol

5

What is the IUPAC name for isopropyl alcohol?

A

1-Propanol

B

2-Propanol

C

1-Butanol

D

2-Butanol

6

When naming unsaturated alcohols, which group gets the lower number?

A

The double bond

B

The longest chain

C

The hydroxyl group

D

The methyl group

7

Methanol is industrially prepared from carbon monoxide and what other reactant?

A

Methane

B

Water

C

Hydrogen

D

Ethane

8

The catalyst used in the industrial preparation of methanol from CO and H2 is?

A

ZnO + Cr2O3

B

Fe2O3

C

NiO

D

Pt

9

What is the optimum temperature range for the process of fermentation?

A

0-10°C

B

15-20°C

C

25-35°C

D

40-50°C

10

In Pakistan, ethanol is commonly prepared by the fermentation of?

A

Fruit juices

B

Starch grains

C

Molasses

D

All of the above

11

The enzyme that converts glucose into ethanol and carbon dioxide is?

A

Diastase

B

Invertase

C

Maltase

D

Zymase

12

The concentration of alcohol obtained by fermentation never exceeds which percentage?

A

10%

B

12%

C

14%

D

20%

13

95% ethyl alcohol is commonly known as?

A

Absolute alcohol

B

Methylated spirit

C

Rectified spirit

D

Denatured alcohol

14

What is added to ethanol for denaturing to create methylated spirit?

A

10% Methanol

B

10% Acetone

C

10% Pyridine

D

10% Benzene

15

The solubility of alcohols in water is due to?

A

Covalent bonding

B

Ionic bonding

C

Hydrogen bonding

D

van der Waals forces

16

The boiling points of alcohols are higher than corresponding alkanes due to?

A

Ionic bonds

B

Larger molecular size

C

Hydrogen bonding

D

Higher density

17

When a nucleophile attacks an alcohol, which bond is likely to break?

A

O-H bond

B

C-H bond

C

C-O bond

D

C-C bond

18

What is the order of reactivity of alcohols when the C-O bond breaks?

A

Primary > Secondary > Tertiary

B

Tertiary > Secondary > Primary

C

Secondary > Tertiary > Primary

D

Primary > Tertiary > Secondary

19

Oxidation of a primary alcohol with acidified dichromate first yields?

A

A ketone

B

An aldehyde

C

An ether

D

An alkene

20

Oxidation of 2-Propanol (a secondary alcohol) yields?

A

Propanal

B

Propanoic acid

C

Propanone (acetone)

D

Propene

21

Tertiary alcohols are resistant to oxidation and undergo what reaction instead?

A

Substitution

B

Addition

C

Esterification

D

Elimination

22

Dehydration of ethanol at 180°C with concentrated H2SO4 gives?

A

Diethyl ether

B

Ethene

C

Ethane

D

Ethyl acetate

23

Reacting ethanol with concentrated H2SO4 at 140°C produces?

A

Ethene

B

Ethanal

C

Diethyl ether

D

Ethyl hydrogen sulphate

24

The Lucas test is used to distinguish between what?

A

Alcohols and phenols

B

Aldehydes and ketones

C

Primary, secondary, and tertiary alcohols

D

Alcohols and ethers

25

In the Lucas test, which type of alcohol forms an oily layer of alkyl halide immediately?

A

Primary alcohol

B

Secondary alcohol

C

Tertiary alcohol

D

All of them

26

Which test can be used to distinguish between methanol and ethanol?

A

Lucas test

B

Tollen's test

C

Benedict's test

D

Iodoform test

27

Phenol is also known by the name?

A

Cresylic acid

B

Benzoic acid

C

Carbolic acid

D

Salicylic acid

28

In Dow's method, phenol is prepared from which starting material?

A

Benzene

B

Chlorobenzene

C

Aniline

D

Benzene sulphonic acid

29

Phenol is acidic, but it is less acidic than?

A

Alcohols

B

Water

C

Carboxylic acids

D

Ethers

30

The dissociation constant (Ka) of phenol is approximately?

A

1.3 x 10^-5

B

1.3 x 10^-8

C

1.3 x 10^-10

D

1.3 x 10^-12

31

The acidic nature of phenol is due to the stability of which ion?

A

Hydroxide ion

B

Phenate ion

C

Phenoxide ion

D

Carbonate ion

32

The reaction of phenol with acetyl chloride in the presence of a base is an example of?

A

Nitration

B

Esterification

C

Alkylation

D

Sulphonation

33

Phenol reacts with dilute HNO3 at 25°C to produce a mixture of?

A

o-Nitrophenol and p-Nitrophenol

B

m-Nitrophenol

C

2,4-Dinitrophenol

D

Picric acid

34

The reaction of phenol with concentrated HNO3 yields which explosive compound?

A

Trinitrotoluene (TNT)

B

2,4,6-Trinitrophenol (Picric acid)

C

Nitrobenzene

D

Nitroglycerine

35

Reacting an aqueous solution of phenol with bromine water gives a white precipitate of?

A

o-Bromophenol

B

p-Bromophenol

C

A mixture of o- and p-Bromophenol

D

2,4,6-Tribromophenol

36

Phenol reacts with formaldehyde in the presence of an acid or alkali to form a polymer called?

A

Nylon

B

Polythene

C

Bakelite

D

Teflon

37

Ethers containing two identical alkyl groups are called?

A

Mixed ethers

B

Unsymmetrical ethers

C

Simple ethers

D

Complex ethers

38

The IUPAC name for diethyl ether is?

A

Methoxy methane

B

Ethoxy ethane

C

Propoxy propane

D

Methoxy ethane

39

Williamson's synthesis is used to prepare?

A

Alcohols

B

Phenols

C

Ethers

D

Aldehydes

40

The first step in Williamson's synthesis involves reacting an alcohol with what to form an alkoxide?

A

An alkyl halide

B

Metallic sodium

C

A mineral acid

D

Water

41

Ethers are generally inert to which of the following reagents in a cold state?

A

Dilute acids

B

Alkalies

C

Metallic sodium

D

All of the above

42

Ethers react with hot hydrogen iodide (HI) to form an alcohol and?

A

An alkene

B

An alkane

C

An alkyl iodide

D

An acid

43

What is the common name for C6H5OH?

A

Benzyl alcohol

B

Phenol

C

Cresol

D

Anisole

44

The conversion of starch to maltose is catalyzed by which enzyme from yeast?

A

Zymase

B

Invertase

C

Maltase

D

Diastase

45

The dehydration of alcohols is what type of reaction?

A

Substitution

B

Addition

C

Elimination

D

Oxidation

46

Which of the following compounds has the highest boiling point?

A

Ethane

B

Diethyl ether

C

Ethanol

D

Chloroethane

47

Carbolic acid was first obtained from?

A

Wood

B

Petroleum

C

Coal tar

D

Fermentation

48

The reaction of phenol with zinc dust results in the formation of?

A

Toluene

B

Benzene

C

Cyclohexanol

D

Aniline

49

Which of the following is used as an antifreeze in automobile radiators?

A

Phenol

B

Methanol

C

Diethyl ether

D

Acetone