Chemistry MCQs Class 11 – Page 3 – Quiz

When air is bubbled through pure water, its pH is lowered from 7.0 to 5.6. Which gas in the air is mainly responsible for this change?

(A) CO₂
(B) NO₂
(C) O₂
(D) H₂

Answer: (A) CO₂

If the given reaction is at equilibrium and its pressure is increased, what would happen?

(A) The concentration of NH₃ will be increased
(B) The concentration of N₂ will be increased
(C) The concentration of H₂
(D) No effect on the concentration of reactant or product will be observed

Answer: (D) No effect on the concentration of reactant or product will be observed

The solids in which atoms, ions or molecules have random non repetitive three dimensional arrangements are called:

(A) Crystals
(B) Glasses
(C) Alloys
(D) Amalgams

Answer: (A) Crystals

Which of the following has maximum boiling point?

(A) C₁₀H₂₂
(B) C₆H₁₄
(C) C₅H₁₂
(D) C₄H₁₀

Answer: (A) C₁₀H₂₂

The Rate of diffusion or effusion of a gas is:

(A) Directly proportional to the square root of its density
(B) Directly proportional to the square of its density
(C) Inversely proportional to the square of its density
(D) Inversely proportional to the square root of its density

Answer: (D) Inversely proportional to the square root of its density