JEE Main, NEET MCQs Set 12

Sr. No.

Question

Answer

1.

In Dumas’ method of estimation of nitrogen 0.35 g of an organic compound gave 55 mL of nitrogen collected at 300 K temperature and 715 mm pressure. The percentage composition of nitrogen in the compound would be

(Aqueous tension at 300 K = 15 mm)

(A) 14.45

(B) 15.45

(C) 16.45

(D) 17.45

Answer: (C)

2.

In Kjeldahl’s method, ammonia from 5 g of food neutralizes 30 cm³ of 0.1 N acid. The percentage of nitrogen in the food is ______.

(A) 8.4

(B) 0.84

(C) 1.68

(D) 16.8

Answer: (B)

3.

In order to increase the volume of a gas by 10%, the pressure of the gas should be

(A) increased by 10 %

(B) increased by 1 %

(C) decreased by 10 %

(D) decreased by 1 %

Answer: (C)

4.

In the brown ring test, the brown colour of the ring is due to

(A) ferrous nitrate

(B) ferric nitrate

(C) a mixture of NO and NO2

(D) nitrosoferrous sulphate

Answer: (D)

5.

In the electrolytic refining of Zinc, ______.

(A) the impure metal is at the cathode.

(B) graphite is at the anode.

(C) acidified zinc sulphate.is the electrolyte.

(D) the metal ion gets reduced at the anode.

Answer: (C)

6.

In the ionic equation – Bi  + 6H⁺ + Xe^– → Bi³⁺ + 3H₂O, the values of X is

(A) 3

(B) 4

(C) 2

(D) 6

Answer: (C)

7.

In the periodic table metals usually used as catalysts belong to

(A) s – block

(B) p – block

(C) d – block

(D) f – block

Answer: (C)

8.

In which of the following process, a maximum increase in entropy is observed?

(A) dissolution of salt in water

(B) condensation of water

(C) sublimation of naphthalene

(D) melting of ice

Answer: (C)

9.

In which of the following, NH₃ is not used?

(A) Group reagent for the analysis of IV group basic radical.

(B) Group reagent for the analysis of IIIgroup basic radical.

(C) T0llen’s reagent

(D) Nessler’s reagent

Answer: (D)

10.

In which one of the following, does the given amount of chlorine exert the least pressure in a vessel of capacity 1 dm³ at 273K?

(A) 0.071 g

(B) 0.0355 g

(C) 0.02 mole

(D) 6.023 x 10²¹ molecules

Answer: (B)