Explore topic-wise MCQs in Current Affairs.

This section includes 2539 Mcqs, each offering curated multiple-choice questions to sharpen your Current Affairs knowledge and support exam preparation. Choose a topic below to get started.

2401.

The substrate must have the correct

A. size to fit the active site of the enzyme only
B. shape to fit the active site of the enzyme only
C. order to fit in the active site
D. size and shape to fit the active site of the enzyme
Answer» E.
2402.

Due to the presence of double bonds, alkenes are

A. unsaturated
B. saturated
C. polar
D. non-polar
Answer» B. saturated
2403.

Alcohols are produced by passing alkenes through

A. steam
B. acid
C. base
D. alkali
Answer» B. acid
2404.

Two stereoisomer's have completely different

A. arrangement of atoms
B. physical properties
C. chemical properties
D. all of above
Answer» E.
2405.

Benzene reacts with bromine in the presence of an anhydrous iron bromide(III) catalyst to give

A. electrophilic substitution
B. addition reaction
C. nucleophilic substitution
D. none of above
Answer» B. addition reaction
2406.

Value of pH is determined by

A. pH electrode
B. pH detector
C. pH balancer
D. pH spectrometer
Answer» B. pH detector
2407.

Useful alkenes for chemical industries is supplied by

A. oil refineries
B. coal mines
C. oil wells
D. flour mill
Answer» B. coal mines
2408.

A primary amine is made from ammonia molecule with its H atom replaced by

A. alkyl group only
B. aryl group only
C. amine group
D. alkyl and aryl group
Answer» E.
2409.

Number of atoms or molecule present in one molar mass of an entity is known as

A. Bohr number
B. Mass number
C. Avogadro's number
D. Atomic number
Answer» D. Atomic number
2410.

Liquid Carbon Dioxide (CO₂(l)) is used in making

A. caffeine
B. decaffeinated tea
C. decaffeinated coffee
D. fat-rich foods
Answer» D. fat-rich foods
2411.

Heating and cooling curves are plots of

A. temperature against mass
B. temperature against kinetic energy
C. available space against kinetic energy
D. temperature against time
Answer» E.
2412.

Due to the presence of lone pair of electrons on nitrogen atom amines and ammonia acts as

A. bases
B. acids
C. alkalis
D. amphoteric
Answer» C. alkalis
2413.

The state which has a regular arrangement and cannot change its shape is

A. solid
B. liquid
C. gas
D. none of above
Answer» B. liquid
2414.

Upon burning, a hydrocarbon releases a lot of

A. carbon dioxide
B. carbon monoxide
C. hydrogen
D. oxygen
Answer» B. carbon monoxide
2415.

If different functional groups are present it is termed as

A. position isomerism
B. functional group isomerism
C. chain isomerism
D. none of above
Answer» C. chain isomerism
2416.

Particles are farthest apart in

A. solids
B. liquids
C. gases
D. all of these
Answer» D. all of these
2417.

If hydrogen and alkene are passed over finely divided nickel, it gives off

A. alcohol
B. alkanes
C. aldehydes
D. ketone
Answer» C. aldehydes
2418.

Unsaturated oils become partially saturated when they are reacted with

A. oxygen
B. hydrogen
C. carbon dioxide
D. carbon monoxide
Answer» C. carbon dioxide
2419.

Some primary amines do not have NH₂ group at the end and are indicated by

A. numbering
B. alphabets
C. roman letters
D. Greek letters
Answer» B. alphabets
2420.

The classes of amines include

A. primary amines
B. secondary amines
C. tertiary amines
D. all of above
Answer» E.
2421.

The symbol used to denote Avogadro's constant is

A. A
B. L
C. V
D. G
Answer» C. V
2422.

Frances Descroizilles in 18th century developed

A. burette
B. pipette
C. beaker
D. measuring cylinder
Answer» C. beaker
2423.

Species having a negative or positive charge are

A. Radicals
B. atoms
C. molecules
D. ions
Answer» E.
2424.

Relative atomic mass of Cu is

A. 61.5
B. 63.5
C. 64.5
D. 67.5
Answer» C. 64.5
2425.

Value of molar volume is

A. 22.14 dm3
B. 25.14 dm3
C. 32.14dm3
D. 44.14dm3
Answer» B. 25.14 dm3
2426.

Atomic mass is mass of carbon taken as

A. 12
B. 13
C. 14
D. 15
Answer» B. 13
2427.

Properties in which isotopes differ are

A. Chemical
B. Physical
C. electrical
D. mechanical
Answer» C. electrical
2428.

C₆H₁₂ is the formula of a

A. cyclohexane
B. sugar
C. alkanes
D. alkenes
Answer» B. sugar
2429.

Liquids may become vapors

A. upon boiling only
B. without boiling
C. at a temperature below the boiling point of a liquid
D. at a temperature above the boiling point of a liquid
Answer» D. at a temperature above the boiling point of a liquid
2430.

Carbon dioxide (CO₂) diffuses

A. slowly than hydrogen
B. slowly than oxygen
C. faster than hydrogen
D. faster than oxygen
Answer» C. faster than hydrogen
2431.

Purity of a substance can be estimated through

A. boiling points
B. melting points
C. sublimation point
D. both a and b
Answer» E.
2432.

Methylated spirit is a form of

A. liquid
B. gas
C. crystal
D. aqueous
Answer» B. gas
2433.

The Russian chemist Dmitri Mendeleev in 1869 devised the

A. Periodic Table
B. Law of thermodynamic
C. law of conservation of energy
D. structure of electron
Answer» B. Law of thermodynamic
2434.

When there is a low concentration of solute in a solution, it is known as

A. diluted solution
B. saturated solution
C. concentrated solution
D. unsaturated solution
Answer» B. saturated solution
2435.

Rate of diffusion is

A. increased if the temperature is increased
B. decreases if the kinetic energy decreases
C. decreases if the molecular mass is increased
D. all of these
Answer» E.
2436.

Ability of dissolving animal fats is found in

A. solid carbon dioxide
B. liquid carbon dioxide
C. gaseous carbon dioxide
D. all of these
Answer» C. gaseous carbon dioxide
2437.

If ethene is a reactant, then the product will be

A. ethanol
B. triol
C. butanol
D. propanol
Answer» B. triol
2438.

A glue hardens when it is squeezed out of tube due to

A. solidification of solvent
B. the evaporation of solvent molecules
C. evaporation of adhesive molecules
D. evaporation of solute particles
Answer» C. evaporation of adhesive molecules
2439.

Phenyl amine reacts with nitrous acid (HNO₂) to form

A. diazonium salt
B. nitric acid
C. sulfuric acid
D. hydrochloric acid
Answer» B. nitric acid
2440.

Enzyme activity refers to the number of

A. moles of enzymes converted to product per minute
B. moles of substrate converted to product per minute
C. substrate molecules reacted per enzyme per minute
D. enzyme reacted on substrate molecule per minute
Answer» C. substrate molecules reacted per enzyme per minute
2441.

Which statement is incorrect about enzymes?

A. they speed up reactions without being used up
B. they raise the activation energy
C. they are all large molecules
D. they are action-specific
Answer» C. they are all large molecules
2442.

Hydrolysis of substituted amides will give the product of

A. carboxylic acids only
B. amines only
C. alcohols
D. carboxylic acids and amines
Answer» E.
2443.

CH₃CONH₂ is formula for

A. amine
B. alkyl
C. methanamide
D. ethanamide
Answer» E.
2444.

Avogadro's constant is the number

A. 6.02 x 10²³
B. 6.03 x 10³²
C. 1.2 x 10⁶
D. 1.23 x 10⁶²
Answer» B. 6.03 x 10³²
2445.

Instrument use to collect ions is

A. Electrometer
B. ionizer
C. spectrometer
D. nanometer
Answer» B. ionizer
2446.

Atomic mass of phosphorus is

A. 11
B. 21
C. 31
D. 41
Answer» D. 41
2447.

John Dalton evidenced existence of atoms in

A. 1808
B. 1898
C. 1838
D. 1856
Answer» B. 1898
2448.

Gas molecules differ in their diameters from distance by

A. 400
B. 300
C. 600
D. 500
Answer» C. 600
2449.

Theoretical yield is decreased by

A. distillation
B. reaction
C. weighing
D. reactants
Answer» B. reaction
2450.

Number of isotopes occupied by carbon is

A. three
B. seven
C. five
D. six
Answer» B. seven