Chemistry Model Question Paper - MCQs Test 34

Sr. No.

Question

Answer

1.

The amount of heat evolved when 500 cm³ of 0.1 M HCl is mixed with 200 cm³ of 0.2 M NaoH is

(A) 2.292 kJ

(B) 1.292 kJ

(C) 22.9 kJ

(D) 0.292 kJ

Answer: (A)

2.

The amount of the heat released when 20 ml 0.5 M NaOH is mixed with 100 ml 0.1 M HCI is ´ kJ. The heat of neutralization is

(A) –100 x kJ/mol

(B) –50 x kJ/mol

(C) +100 x kJ/mol

(D) +50 x kJ/mol

Answer: (A)

3.

The atomic numbers of Ni and Cu are 28 and 29 respectively. The electron configuration 1s² 2s² 2p⁶ 3s² 3p⁶ 3d¹⁰ represents

(A) Cu⁺

(B) Cu²⁺

(C) Ni²⁺

(D) Ni

Answer: (A)

4.

The basicity of aniline is less than that of cyclohexylamine. This is due to

(A) +R effect of -NH₂ group

(B) -I effect of -NH₂ group

(C) -R effect of -NH₂ group

(D) hyperconjugation effect

Answer: (A)

5.

The brown ring test for nitrates depends on

(A) the reduction of nitrate to nitric oxide

(B) oxidation of nitric oxide to nitrogen dioxide

(C) reduction of ferrous sulphate to iron

(D) oxidising action of sulphuric acid

Answer: (A)

6.

The catalyst used in the preparation of an alkyl chloride by the action of dry HCI on an alcohol is

(A) anhydrous AlCl₃

(B) FeCl₃

(C) anhydrous ZnCl₂

(D) Cu

Answer: (C)

7.

The compound which gives turbidity immediately with Lucas reagent at room temperature is ______.

(A) butan-2-ol

(B) butan-1-ol

(C) 2-methyl propan-1-ol

(D) 2-methyl propan-2-ol

Answer: (D)

8.

The concentration of a reactant X decreases from 0.1 M to 0.025 M in 40 minutes. If the

reaction follows I order kinetics, the rate of the reaction when the concentration of X is

0.01 M will be

(A) 1.73 ´ 10^-4 M min^-l

(B) 2.47 ´ 10^-4 M min^-l

(C) 3.47 ´ 10^-5 M min^-l  

(D) 1.73 ´ 10^-5 M min^-l

Answer: (B)

9.

The conversion of m-nitrophenol to resorcinol involves respectively

(A) diazotization, reduction and hydrolysis

(B) hydrolysis, diazotization and reduction

(C) reduction, diazotization and hydrolysis

(D) hydrolysis, reduction and diazotization

Answer: (C)

10.

The correct decreasing order of dipole moment in CH₃CI, CH₃Br and CH₃F is

(A) CH₃F > CH₃CI > CH₃Br

(B) CH₃F > CH₃Br > CH₃CI

(C) CH₃CI> CH₃F > CH₃Br

(D) CH₃CI> CH₃Br > CH₃F

Answer: (C)

11.

The decomposition of a certain mass of CaCO₃ gave 11.2 dm³ of CO₂ gas at STP. The mass of KOH required to completely neutralise the gas is

(A) 56 g

(B) 28 g

(C) 42 g

(D) 20 g

Answer: (A)

12.

The density of a gas is 1.964 g dm^-1 at 273 k and 76 cm Hg. The gas is

(A) CH₄

(B) C₂H₆

(C) CO₂

(D) Xe

Answer: (C)

13.

The electronic transitions from n = 2 to n = 1 will produce shortest wavelength in (where n = principal quantum state)

(A) Li⁺²

(B) He⁺

(C) H

(D) H⁺

Answer: (A)

14.

The empirical formula of a nonelectrolyte is CH₂O. A solution containing 3g of the compound exerts the same osmotic pressure as that of 0.05 M glucose solution. The molecular formula of the compound is

(A) C₂H₄O₂

(B) CH₂O

(C) C₃H₆O₃

(D) C₄H₈O₄

Answer: (A)

15.

The energy of an electron in first Bohr orbit of H – atom is – 13.6 eV. The possible energy value of electron in the excited state of Li²⁺ is

(A) –122.4 eV

(B) 30.6 eV

(C) –30.6 eV

(D) 13.6 eV

Answer: (C)