Which of the following gases has the lowest rate of diffusion?

[H=1.0, C=12.0, N = 14.0, O= 16.0]

• A. Nitrogen
• B. methane
• C. Ammonia
• D. Oxygen

SO3 is NOT directly dissolved in water in the preparation of H2SO4 by the contact process because?

• A. the reaction between SO3 and water is violently exothermic
• B. acid is usually added to water and never water to acid
• C. SO3 does not dissolve in water readily
• D. SO3 is an acid gas

Which of the following pollutants will lead to the depletion of ozone layer?

• A) chlorofluorocarbon
• B) carbon (ii) oxide
• C) hydrogen sulphide
• D) sulphur (iv) oxide

Which of these catalysts is used for hydrogenation of alkene?

• A) H₂
• B) Na
• C) Pd
• D) Hg

Calcium atom ionizes by

• A) gaining two electrons
• B) losing two electrons
• C) sharing two electrons
• D) gaining two proton

Consider the reaction represented by the following equation: C₂H₂ + yH₂ → C₂H₆. The value of y in the reaction is

• A. 4
• B. 3
• C. 2
• D. 1

How many electrons are in the L shell of₁₅³¹P?

• A. 5
• B. 8
• C. 18
• D. 2

Which of the following properties is/are not exhibited by catalysts

• A. Altering the rate of a chemical reaction
• B. Same mass and composition of the end of reaction
• C. Causing a change in the equilibrium portion of a reversible reaction
• D. Causing off a reaction which will normally not occur

Zn + CuSO₄ → ZnSO₄ + Cu

• A. Cu
• B. Zn
• C. ZnSO₄
• D. CuSO₄

Which of the following CANNOT be an empirical formula?

• A. CH
• B. CH₂
• C. P₂O₅
• D. N₂O₄