chemistry MCQs - 10th class Chapter 03 Mcqs

1

The theory that organic compounds could only be synthesized within living things was known as?

A

Catenation Theory

B

Vital Force Theory

C

Molecular Theory

D

Atomic Theory

2

Who was the first chemist to synthesize an organic compound, urea, in a laboratory?

A

Jacob Berzelius

B

Kolbe

C

Friedrich Wöhler

D

Lavoisier

3

What is the essential element present in all organic compounds?

A

Oxygen

B

Nitrogen

C

Hydrogen

D

Carbon

4

The branch of chemistry dealing with hydrocarbons and their derivatives is called?

A

Inorganic Chemistry

B

Physical Chemistry

C

Biochemistry

D

Organic Chemistry

5

Which type of formula represents the actual number of atoms in one molecule?

A

Structural Formula

B

Condensed Formula

C

Molecular Formula

D

Electronic Formula

6

Compounds having the same molecular formula but different structural formulae are called?

A

Isotopes

B

Allotropes

C

Isomers

D

Polymers

7

The ability of carbon atoms to link with other carbon atoms to form long chains and large rings is called?

A

Isomerism

B

Catenation

C

Polymerization

D

Hydrogenation

8

Which of the following is a characteristic of organic compounds?

A

High melting points

B

Good conductors of electricity

C

Generally soluble in water

D

Generally have low melting points

9

Open chain compounds are also known as?

A

Acyclic compounds

B

Cyclic compounds

C

Aromatic compounds

D

Heterocyclic compounds

10

Which of the following is an example of a homocyclic aromatic compound?

A

Cyclobutane

B

Pyridine

C

Benzene

D

Thiophene

11

Heterocyclic compounds contain at least one atom in the ring that is not?

A

Hydrogen

B

Carbon

C

Oxygen

D

Nitrogen

12

The main reason carbon shows catenation while silicon does not is because?

A

Si-Si bonds are stronger than C-C bonds

B

C-C bonds are stronger than C-O bonds

C

C-C bonds are much stronger than Si-Si bonds

D

Silicon has a valency less than two

13

The process of conversion of wood into coal is called?

A

Destructive Distillation

B

Carbonization

C

Fractional Distillation

D

Polymerization

14

Which type of coal has the highest carbon content?

A

Peat

B

Lignite

C

Bituminous

D

Anthracite

15

The strong heating of coal in the absence of air is known as?

A

Carbonization

B

Combustion

C

Destructive Distillation

D

Calcination

16

Which product of destructive distillation is a thick black liquid containing over 200 organic compounds?

A

Coal Gas

B

Coke

C

Ammonical Liquor

D

Coal Tar

17

What is the main component of natural gas, making up about 85%?

A

Ethane

B

Methane

C

Propane

D

Butane

18

The general formula for alkanes is?

A

CnH2n

B

CnH2n-2

C

CnH2n+2

D

CnHn

19

Alkyl radicals are formed by the removal of one ________ atom from an alkane.

A

carbon

B

hydrogen

C

oxygen

D

nitrogen

20

The functional group -OH is characteristic of which class of organic compounds?

A

Ethers

B

Aldehydes

C

Alcohols

D

Ketones

21

The functional group C-O-C represents?

A

Esters

B

Ethers

C

Ketones

D

Alcohols

22

Which functional group is present in carboxylic acids?

A

-CHO

B

-OH

C

-COOH

D

-CO-

23

What is the molecular formula for butane?

A

C3H8

B

C4H10

C

C5H12

D

C4H8

24

The food we eat, such as carbohydrates, proteins, and fats, are all examples of?

A

Inorganic compounds

B

Acids

C

Bases

D

Organic compounds

25

In the test for unsaturation, the decolorization of what substance indicates a positive result?

A

Litmus solution

B

Bromine water

C

Fehling's solution

D

Sodium metal

26

Which test results in a 'fruity smell' for a positive outcome?

A

Sodium metal test

B

Litmus test

C

Ester formation test

D

Baeyer's test

27

CO2 gas with effervescence evolves when a carboxylic acid is treated with?

A

NaOH solution

B

NaHCO3 solution

C

KMnO4 solution

D

Phenyl hydrazine

28

What is the functional group for amines?

A

-NH2

B

-COOH

C

-OH

D

-X

29

The general formula for alkyl radicals is?

A

CnH2n+2

B

CnH2n

C

CnH2n+1

D

CnH2n-1

30

The number of isomers increases with the increase in the number of?

A

hydrogen atoms

B

carbon atoms

C

oxygen atoms

D

bonds

31

Organic compounds are generally poor conductors of electricity due to the presence of?

A

Ionic bonds

B

Metallic bonds

C

Covalent bonds

D

Hydrogen bonds

32

Which of the following is a source of organic compounds from dead plants?

A

Proteins

B

Vitamins

C

Coal

D

Gums

33

Coke, a residue from destructive distillation, is approximately what percentage of carbon?

A

60%

B

70%

C

80%

D

98%

34

Petroleum is separated into fractions using which technique?

A

Destructive distillation

B

Steam distillation

C

Filtration

D

Fractional distillation

35

The basic unit of all types of carbohydrates, synthesized by plants, is?

A

Sucrose

B

Glucose

C

Starch

D

Cellulose

36

What is the functional group of an ester?

A

R-O-R'

B

R-COOH

C

R-COOR'

D

R-CHO

37

The reaction of an alcohol with a piece of sodium metal evolves which gas?

A

Oxygen

B

Carbon dioxide

C

Nitrogen

D

Hydrogen

38

A red precipitate in Fehling's solution test indicates the presence of which functional group?

A

Ketonic group

B

Aldehydic group

C

Carboxyl group

D

Alcoholic group

39

A compound with a triple bond between two carbon atoms is called an?

A

Alkane

B

Alkene

C

Alkyne

D

Alcohol

40

What is the name of the C2H5- radical?

A

Methyl

B

Ethyl

C

Propyl

D

Butyl

41

The molecular formula for decane is?

A

C9H20

B

C10H22

C

C10H20

D

C8H18

42

Which of these is an example of a branched-chain compound?

A

n-Butane

B

n-Pentane

C

Isobutane

D

Propane

43

Compounds like pyridine and thiophene are classified as?

A

Aromatic

B

Alicyclic

C

Homocyclic

D

Heterocyclic

44

The carbon-carbon bond energy is approximately?

A

200 kJ mol-1

B

452 kJ mol-1

C

355 kJ mol-1

D

351 kJ mol-1

45

Acetylene is an example of a molecule with a?

A

Single covalent bond

B

Double covalent bond

C

Triple covalent bond

D

Ionic bond

46

Which of the following is NOT a product of the destructive distillation of coal?

A

Coal gas

B

Petroleum

C

Coke

D

Coal Tar

47

The term 'paraffins' refers to which group of hydrocarbons?

A

Alkenes

B

Alkynes

C

Alkanes

D

Aromatics

48

Successive members of a homologous series differ by which unit?

A

-CH3-

B

-CH2-

C

-CH-

D

-C-

49

What is the functional group for alkyl halides?

A

-OH

B

-X

C

-NH2

D

-COOH

50

In Baeyer's test for unsaturation, the disappearance of the pink color of which substance indicates a positive result?

A

Bromine water

B

Fehling's solution

C

Alkaline KMnO4

D

Sodium nitroprusside