The constituent of air that acts as a diluent is

• A) nitrogen
• B) carbon (IV) oxide
• C) noble gases
• D) oxygen

Aluminium is extracted from

• A. magnetite
• B. cryolite
• C. bauxite
• D. cassiterite

What is the effect of using vanadium (V) oxide as catalyst in the reaction represented by the following equation? 2SO₂ + O2 ⇌ 2SO₃; ΔH = - xKJmol-1

• A. Decreases the value of ΔH
• B. Increases the collision rate of reactant particles
• C. Shifts equilibrium position to the right
• D. Reduces the time for attainment of equilibrium

(a) When MgSO\(_4\).XH\(_2\)O crystals were exposed to the atmosphere for several days, three was a loss in mass

(i) What name is given to this phenomenon?

(ii) Give another example of a compound that exhibits this phenomenon

(b) If 0.50 mole of MgSO\(_4\).XH\(_2\)O has a mass of 123g. calculate the value of X. (H = 1, O = 16, Mg = 24, S = 32)

In what way is equilibrium constant for the forward reaction related to that of the reversed reaction?

• A. The additional of the two is expected to be one
• B. The product of the two is expected to be one
• C. The two equilibrium constants are identical
• D. The product of the two is always greater than one

A substance responsible for the sour taste of unripe orange is

• A. Alkene
• B. Alkanol
• C. Alkanoic acid
• D. Alkanoate

Given the following half-cell reaction; 2Cl(aq) → CI₂(g) + 2e, how many mole of electrons will be required to produce 1.12dm³of chlorine gas at s.t.p? (Molar volume of a gas at s.t.p. = 22.4dm³)

• A. 1.00
• B. 0.40
• C. 0.20
• D. 0.10

Which of the following electronic configurations correctly represents an element in period 3 of the periodic table?

• A. 1s²2s²2p²
• B. 1s²2s²2p⁶
• C. 1s²2s²2p⁶3s²3p⁴
• D. 1s²2s²2p⁶3s²3p⁶4s¹

Which of these salts will produce its metal, oxygen and nitrogen (IV) oxide on heating?

• A. Silver and trioxonitrate (V)
• B. Sodium trioxonitrate (V)
• C. Calcium trioxonitrate (V)
• D. Lithium trioxonitrate (V)

When an ionic bond is broken, bonding electrons are

• A. shared between participating atoms
• B. gained by the most electropositive atom
• C. gained by the most electronegative atom
• D. lost by both participating atoms.