set 2 MCQ Questions & Answers Detailed Explanation

Question : 1

An organic compound containing C, H and N gave the following analysis : C = 40% ; H = 13.33% ; N = 46.67% Its empirical formula would be

a) CH₄N

b) C₂H₇N₂

c) CH₅N

d) C₂H₇N

Question : 2

Which of the following is not an endothermic process?

a) Dissolving conc. H₂ SO₄ in water

b) Boiling of water

c) Dissolving salts in water

d) Evaporation of water

Question : 3

Chemical equations are balanced in accordance with the

a) Law of definite composition

b) Dalton’s law

c) Law of conservation of mass

d) None of these

Question : 4

Which of the following is most unreactive ?

a) Mg²⁺

b) Mg

c) Mg⁺

d) All above species are inert

Question : 5

Which of the following involves combination of two elements?

a) 2SO₂ + O₂ ⟶ 2SO₃

b) CaO + CO₂ ⟶ CaCO₃

c) 4Na + O₂ ⟶ 2Na₂O

d) NH₃ + HCl ⟶ NH₄Cl

Question : 6

The reactions in which two compounds exchange their radicals to form two new compounds are called

a) double displacement reaction

b) displacement reaction

c) decomposition reaction

d) isomerisation reaction