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.

201.

A compound X with molecular formula C3H8O can be oxidised to a compound Y with the molecularformula C3H6O2 X is most likely to be …..

A. Primary alcohol
B. Secondary alcohol
C. Aldehyde
D. Ketone
Answer» B. Secondary alcohol
202.

Paraffin wax is………..

A. Ester
B. Alcohol
C. Unsaturated hydrocarbon
D. Saturated Hydrocrabon
Answer» E.
203.

Which of the following does not turn Schiff's reagent to pink…………

A. Formaldehyde
B. Benzaldehyde
C. Acetone
D. Acetaldehyde
Answer» D. Acetaldehyde
204.

The petrol having octane number 80 has…………

A. 20% normal heptane + 80% iso-octane
B. 80% normal heptane + 20% iso-octane
C. 20% normal heptane + 80% normal octane
D. 80% normal heptane + 20% normal octane
Answer» B. 80% normal heptane + 20% iso-octane
205.

Which of the following is a mixed ketone ………..

A. Pentanone
B. Acetophenone
C. Benzophenone
D. Butanone
Answer» B. Acetophenone
206.

Glycerol is not used in which of following cases…….

A. Explosive making
B. Shaving soap making
C. As an antifreeze for water
D. As an antiseptic agent
Answer» E.
207.

Aqueous solution of the following compound on electrolysis gives ethane……….

A. Acetic acid
B. Acetamide
C. Potassium acetate
D. Ethyl acetate
Answer» D. Ethyl acetate
208.

Which is primary alcohol…….

A. Butane-2-ol
B. Butane-1-ol
C. Propane-2-ol
D. Isopropyl alcohol
Answer» C. Propane-2-ol
209.

In alkanes, the bond angle is……..

A. 109.5 o
B. 109 o
C. 120 o
D. 180 o
Answer» B. 109 o
210.

On heating glycerol with conc. H2SO4 a compound is obtained which has a bad odour. The compoundis…..

A. Glycerol sulphate
B. Acrolein
C. Formic acid
D. Allyl alcohol
Answer» C. Formic acid
211.

Glycerol is used in the manufacture of

A. Dynamite
B. Varnish
C. Paints
D. Soft drinks
Answer» B. Varnish
212.

Formation of alkane by the action of Zn on alkyl halide is called

A. Frankland's reaction
B. Wurtz reaction
C. Cannizzaro reaction
D. Kolbe's reaction
Answer» B. Wurtz reaction
213.

The process of manufacture of absolute alcohol from rectified spirit is…….

A. Fractional distillation
B. Steam distillation
C. Azeotropic distillation
D. Vacuum distillation
Answer» D. Vacuum distillation
214.

Which one of the following reacts with HCN and Tollen's reagent, but is not oxidised by Fehling'ssolution……………

A. Methanal
B. Ethanal
C. Benzaldehyde
D. Acetone
Answer» D. Acetone
215.

Which of the following does not give yellow precipitate with KINaOH…………

A. Acetone
B. Acetaldehyde
C. Benzaldehyde
D. Acetophenone
Answer» D. Acetophenone
216.

Iso-octane is mixed to the petrol………….

A. To precipitate inorganic substances
B. To prevent freezing of petrol
C. To increase boiling point of petrol
D. As an antiknock
Answer» E.
217.

Dry heating of calcium acetate gives

A. Acetaldehyde
B. Ethane
C. Acetic acid
D. Acetone
Answer» E.
218.

Amongst the following, HBr reacts fastest with…….

A. Propane-1-ol
B. Propane-2-ol
C. 2-methyl propane-1-ol
D. 2-methyl propane-2-ol
Answer» E.
219.

For C2H5 CHO which of the following is incorrect……….

A. On oxidation it yields benzoic acid
B. It is used in perfumery
C. It is an aromatic aldehyde
D. On reduction yields phenol
Answer» E.
220.

The order of appearance of the following with rising temperature during the refining of crude oil is…..…......

A. Kerosene oil, gasoline, diesel
B. Diesel, gasoline, kerosene oil
C. Gasoline, diesel, kerosene oil
D. Gasoline, kerosene oil, diesel
Answer» E.
221.

The natural petroleum contains………….

A. Saturated hydrocarbons
B. Cyclic saturated hydrocarbons
C. Compounds of sulphur
D. All of these
Answer» E.
222.

2-Methylbutane on reacting with bromine in the presence of sunlight gives mainly……..

A. 1-bromo-2-methylbutane
B. 2-bromo-2-methylbutane
C. 2-bromo-3-methylbutane
D. 1-bromo-3-methylbutane
Answer» C. 2-bromo-3-methylbutane
223.

The product formed in aldol condensation is…………….

A. Beta hydroxy acid
B. Beta hydroxy aldehyde or ketone
C. Alpha, beta unsaturated ester
D. Alpha, hydroxy aldehyde or ketone
Answer» C. Alpha, beta unsaturated ester
224.

On mixing tetraethyl lead to gasoline available at petrol pumps…………..

A. Calorific value of the fuel increases
B. Odour diminishes
C. Less smoke is obtained on combustion
D. Antiknock property of fuel increases
Answer» E.
225.

Isopropyl alcohol on oxidation forms……

A. Acetone
B. Ether
C. Ethylene
D. Acetaldehyde
Answer» B. Ether
226.

Gasoline is a mixture of alkanes with the number of carbon atoms …………….

A. C3 + C5
B. C5 + C6
C. C6 + C8
D. C7 + C9
Answer» E.
227.

Water gas is………..

A. CO + CO2
B. CO + N2
C. CO + H2
D. CO + N2 + H2
Answer» D. CO + N2 + H2
228.

The final product formed when acetaldehyde is reduced with sodium and alcohol is…………

A. Ethylene
B. Ethyl alcohol
C. Ethene
D. All of these
Answer» C. Ethene
229.

In which of the following reaction new carbon carbon bond is not formed?

A. Cannizzaro reaction
B. Friedel craft reaction
C. Wurtz reaction
D. Aldol condensation
Answer» B. Friedel craft reaction
230.

Aldehyde turns pink with ………….

A. Benedict solution
B. Schiff reagent
C. Fehling solution
D. Tollen's reagent
Answer» C. Fehling solution
231.

Which of the following does not decolourise bromine solution in carbon disulphide………..

A. Acetylene
B. Propene
C. Ethane
D. Propyne
Answer» D. Propyne
232.

Ethyl alcohol is industrially prepared from ethylene by……..

A. Permanganate oxidation
B. Catalytic reduction
C. Absorbing in H2SO4 followed by hydrolysis
D. Fermentation
Answer» D. Fermentation
233.

Which compound is not inflammable………..

A. CCl4
B. C2H5OH
C. CH4
D. C6H6
Answer» B. C2H5OH
234.

Which one gives only one monosubstitution product on chlorination………..

A. n-pentane
B. (b) Neopentane
C. (c) Isopentane
D. (d) n-butane
Answer» C. (c) Isopentane
235.

In the reaction CH3- Br+ 2Na+ Br-CH3 , the product called ……..

A. Wurtz reaction
B. Aldol condensation
C. Perkin’s reaction
D. Levit reaction
Answer» B. Aldol condensation
236.

Most of the hydrocarbons from petroleum are obtained by…………….

A. Fractional distillation
B. Fractional crystallization
C. Vaporization
D. Polymerization
Answer» B. Fractional crystallization
237.

The product formed by the reaction of chlorine with benzaldehyde in the absence of a catalystis…………..

A. Chlorobenzene
B. Benzyl chloride
C. Benzoyl Chloride
D. o –Chlorobenzaldehyde
Answer» D. o –Chlorobenzaldehyde
238.

Kerosene is a mixture of………….

A. Alkanes
B. Aromatic compounds
C. Alcohols
D. Aliphatic acids
Answer» C. Alcohols
239.

By Wurtz reaction, a mixture of methyliodide and ethyliodide gives………….

A. Butane
B. Ethane
C. Propane
D. A mixture of the above three
Answer» E.
240.

: Power alcohol is ……

A. An alcohol of 95% purity
B. A mixture of petrol hydrocarbons and ethanol
C. Rectified spirit
D. A mixture of methanol and ethanol
Answer» C. Rectified spirit
241.

: In cold countries ethylene glycol is added to water in the radiators to

A. Bring down the specific heat of water
B. Lower the viscosity
C. Reduce the viscosity
D. Make water a better lubricant
Answer» B. Lower the viscosity
242.

Methanol and ethanol are distinguished by the…….

A. Action of HCl
B. Iodoform test
C. Solubility in water
D. Sodium
Answer» C. Solubility in water
243.

Acetaldehyde and acetone can be distinguished by……………

A. Molisch test
B. Bromoform test
C. Solubility in water
D. Tollen's test
Answer» E.
244.

When rectified spirit and benzene are distilled together, the first fraction obtained is……

A. A ternary azeotrope
B. Absolute alcohol
C. A binary azeotrope
D. Denatured spirit
Answer» B. Absolute alcohol
245.

Which of the following will have least hindered rotation about carbon-carbon bond…………

A. Ethane
B. Ethylene
C. Acetylene
D. Hexachloroethane
Answer» B. Ethylene
246.

Which of the following cycloalkane gives open chain compound, when reacts withbromine………..

A. Cyclopropane
B. Cyclopentane
C. Cyclohexane
D. Cyclo-octane
Answer» B. Cyclopentane
247.

Alcohols combine with acetylene in the presence of mercury compounds as catalyst to form…….

A. Acetals
B. Xanthates
C. Vinyl ethers
D. None of the above
Answer» B. Xanthates
248.

LPG is a mixture of………….

A. C6H12+ C6H6
B. C4H10+ C3H8
C. C2H4 + C2H2
D. C2H4 + CH4
Answer» C. C2H4 + C2H2
249.

Which of the following is oxidised by KMnO4

A. Methane
B. Pentane
C. Isobutane
D. Neopentane
Answer» D. Neopentane
250.

Glycerol reacts with potassium bisulphate to produce …………

A. Allyl iodide
B. Allyl sulphate
C. Acryl aldehyde
D. Glycerol trisulphate
Answer» D. Glycerol trisulphate