Explore topic-wise MCQs in Chemistry.

This section includes 155 Mcqs, each offering curated multiple-choice questions to sharpen your Chemistry knowledge and support exam preparation. Choose a topic below to get started.

1.

The general formula for the alkynes is

A. CNH2N+2
B. CNH2N
C. CNH2N-2
D. CNH2N+1
Answer» D. CNH2N+1
2.

The general formula for the alkanes is

A. CNH2N
B. CNH2N+1
C. CNH2N-2
D. CNH2N+2
Answer» E.
3.

How can you determine if a reaction is endothermic?

A. The temperature of the system decreases.
B. The temperature of the system increases.
C. The temperature of the system remains constant.
D. The temperature of the system fluctuates
Answer» B. The temperature of the system increases.
4.

One of the raw materials used in preparing ethyne (C2H2) contains a number of impurities. Two of these impurities are

A. calcium carbonate and calcium phosphide
B. copper sulfate and calcium phosphide
C. calcium sulfide and calcium phosphide
D. calcium sulfide and hydrochloric acid
Answer» D. calcium sulfide and hydrochloric acid
5.

What is the main component of natural gas?

A. Methane
B. Ethane
C. Ethene
D. Propane
Answer» B. Ethane
6.

In a laboratory experiment, students tested the solubility of different solutes in methylbenzene. They made a table as shown. However, two of these results are incorrect. Select the two incorrect results from the list below

A. Cooking oil and water
B. Cyclohexane and iodine
C. Salt water and octane
D. Salt water and cyclohexane
Answer» D. Salt water and cyclohexane
7.

Ethyl halides are reduced by_________ hydrogen.

A. ordinaiy
B. none of above
C. nascent
D. nil
Answer» B. none of above
8.

Ethane is _________ in water.

A. soluble
B. insoluble
C. solvent
D. none of above
Answer» C. solvent
9.

Iodine gives _______product with acetylene.

A. tetra-iodo
B. dia-aiodo
C. none of above
D. di-iodo
Answer» E.
10.

The number of electron in M-shell of an element having atomic number 24 is

A. 11
B. 12
C. 13
D. 10
Answer» D. 10
11.

Methane is oxidized to _________ at 400c° and 200 atm. in presence of Cu

A. none of above
B. nil
C. methanal
D. methanol
Answer» E.
12.

Alkanes ______________ chemically with electrophiles and nucleophiles.

A. do not react
B. react
C. nil
D. none of above
Answer» B. react
13.

The reaction of alkanes with chlorine is _________ than with bromine.

A. none of above
B. lower
C. faster
D. between
Answer» D. between
14.

A source of light is passed through isolated chlorophyll solution.When source is removed, which light is emitted by solution?

A. Red- Orange
B. Green
C. No light is emitted
D. Same as source of light
Answer» C. No light is emitted
15.

On heating a liquid at its dynamic equilibrium the concentration of molecules in vapour state as well as in liquid state

A. Remains constant
B. Neither increase nor decreases
C. Increase
D. Decreases
Answer» B. Neither increase nor decreases
16.

Acetylenic __________ hydrogen atoms are in nature.

A. acidic
B. solvent
C. basic
D. none of above
Answer» B. solvent
17.

The acylation of benzene is called__________ reaction.

A. wurtz
B. ke Wa
C. none of above
D. Friedel and craft
Answer» E.
18.

The _________ directing groups

A. none of above
B. para
C. meta
D. ortho
Answer» C. meta
19.

Benzene was discovered by

A. We ke
B. none of above
C. Faraday
D. ke We
Answer» D. ke We
20.

________is used as a synthetic fibre.

A. nil
B. vinyl acetate
C. acrylonitrile
D. none of above
Answer» D. none of above
21.

Benzene _________ oxidized by kMnO4 or K2Cr2O7

A. is
B. are not
C. none of above
D. is not
Answer» E.
22.

Alkenes__________the colour of basic solution of KMnO

A. charge
B. discharge
C. none of above
D. nil
Answer» E.
23.

Ethylene is a ________ molecule.

A. nil
B. polar
C. none of above
D. nonpolar
Answer» E.
24.

__________group acts as a negative group in Ho x molecules.

A. none of above
B. halogen
C. nil
D. hydroxyl
Answer» E.
25.

Alkanes are __________ in water.

A. none of above
B. soluble
C. insoluble
D. solvent
Answer» D. solvent
26.

Which branched chain isomer of the hydrocarbon with molecular mass 72u gives only one isomer of mono substituted alkyl halide?

A. Isohexane
B. Neopentane
C. Neohexane
D. Tertiary butyl chloride
Answer» C. Neohexane
27.

Benzene is ____________ in alcohol (or in soluble).

A. insoluble
B. soluble
C. none of above
D. solute
Answer» B. soluble
28.

Ozonolysis of an organic compound 'A' produces acetone and propionaldehyde in equimolar mixture. Identify 'A' from the following compounds

A. 2 - Methyl - 2 - pentene
B. 2 - Methyl - 1 - pentene
C. 1 - Pentene
D. 2 - Pentene
Answer» B. 2 - Methyl - 1 - pentene
29.

The angle strain in cyclobutane is

A. 24°44?
B. 29°16?
C. 19°22?
D. 9°44?
Answer» E.
30.

A dibromo derivative of an alkane reacts with sodium metal to form an alicyclic hydrocarbon. The derivative is ______.

A. 2, 2-dibromobutane
B. 1, 4-dibromobutane
C. 1, 1-dibromopropane
D. 1, 2-dibromoethane
Answer» C. 1, 1-dibromopropane
31.

Ethyl benzene CANNOT be prepared by ______.

A. Wurtz-Fittig reaction
B. Clemmensen reduction
C. Wurtz reaction
D. Friedel-Crafts reaction
Answer» D. Friedel-Crafts reaction
32.

The synthesis of 3-octyne is achieved by adding a bromoalkane into a mixture of sodium amide and an alkyne. The bromoalkane and alkyne respectively are

A. BrCH2CH2CH2CH3 and CH2CH2C ? CH
B. BrCH2CH 2CH2CH2CH3 and CH3CH2C ? CH
C. BrCH2CH2CH2CH2CH3 and CH2C ? CH
D. BrCH2CH2CH3 and CH3CH2CH2C ? CH
Answer» B. BrCH2CH 2CH2CH2CH3 and CH3CH2C ? CH
33.

Which one of these is NOT TRUE for benzene?

A. There are three carbon-carbon single bonds and three carbon-carbon double bonds
B. Heat of hydrogenation of benzene is less than the theoretical value
C. The bond angle between carbon-carbon bonds is 120°
D. It forms only one type of monosubstituted product
Answer» B. Heat of hydrogenation of benzene is less than the theoretical value
34.

Among the following compounds the one that is most reactive towards electrophilic nitration is

A. Toluene
B. Benzene
C. Benzoic Acid
D. Nitrobenzene
Answer» B. Benzene
35.

One mole of a symmetrical alkene on ozonolysis gives two moles of an aldehyde having a molecular mass of 44 u. The alkene is

A. Propene
B. 1-butene
C. Ethane
D. 2-butene
Answer» C. Ethane
36.

Ozonolysis of an organic compound gives formaldehyde as one of the products. This confirms the presence of

A. Two ethylenic double bonds
B. A vinyl group
C. An acetylenic triple bond
D. An isopropyl group
Answer» C. An acetylenic triple bond
37.

__________ carbide reacts with water to give methane

A. Calcium
B. Aluminium
C. none of above
D. 1 and 2
Answer» C. none of above
38.

Ethene is slightly_________ in taste.

A. sweet
B. none of above
C. bitter
D. tasteless
Answer» B. none of above
39.

Methane is the ______ component of natural gas:

A. between
B. major
C. minor
D. none of'above
Answer» C. minor
40.

The carbon, carbon bond lengths in benzene are A°

A. 1.54
B. 1.397
C. 1.34
D. none of above
Answer» C. 1.34
41.

The hydrocarbons which contain at least_________benzene ring in their molecules are, called aromatic hydrocarbon.

A. 2
B. 3
C. 1
D. none of above
Answer» D. none of above
42.

Calcium carbide reacts with water to produce

A. none of above
B. nil
C. acetylene
D. ethane
Answer» D. ethane
43.

The old name of alkenes was

A. nil
B. olefin
C. paraffins
D. none of above
Answer» C. paraffins
44.

The hydrocarbon in which all the four valencies of carbon atoms are fully utilized are called________

A. alkanes
B. alkynes
C. alkenes
D. none of above
Answer» B. alkynes
45.

Chlorination of alkanes is an example of________ reaction.

A. none of above
B. elimination
C. redical
D. free redical
Answer» E.
46.

Removal of __ from a molecule is called dehydration.

A. none of above
B. Acid
C. base
D. Water
Answer» E.
47.

Which one of these is not a source of methane gas?

A. Burning coal
B. Refuse dumps
C. Anaerobic decomposition of animal waste
D. Ruminating animals such as cattle, sheep and pigs
Answer» B. Refuse dumps
48.

The formula that shows how atoms are arranged in a molecule is called the

A. actual formula
B. structural formula
C. empirical formula
D. molecular formula
Answer» C. empirical formula
49.

n-Proply bromide on treatment with ethanolic KOH is

A. Propane
B. Propene
C. Propyne
D. Propanal
Answer» C. Propyne
50.

Acetylene is prepared by the action of water on

A. Al4C3
B. Silicon carbide
C. CaC2
D. All of these
Answer» D. All of these