The reaction between sulphur (IV) oxide and oxygen is represented by the equilibrium reaction 2SO_2(g) + O_2(g) ↔ 2SO_3(g), ∆H = -196 kJ. What factor would influence increased production of SO_3(g)?

A. Addition of a suitable catalyst

B. Increase in the temperature of the reaction

C. Decrease in the temperature of the reaction

D. Decrease in the concentration of SO_2(g)

Magnesium ribbon was allowed to burn inside a given gas P leaving a white solid residue Q. Addition of water to Q liberated a gas which produced dense white fumes with a drop of hydrochloric acid. The gas P was?

A. nitrogen

B. chlorine

C. oxygen

D. sulphur (IV) oxide

The best treatment for a student who accidentally poured concentrated tetraoxosulphate (VI) acid on his skin in the laboratory is to wash the skin with?

A. cold water

B. sodium hydroxide solution

C. iodine solution

D. sodium trioxocarbonate (IV) solution

In which of the following pairs of element is allotropy exhibited by each element?

A. Phosphorus and hydrogen

B. Oxygen and chlorine

C. Sulphur and nitrogen

D. Oxygen and sulphur

Which of the following gases can best be used for demonstrating the fountain experiment?
i) Nitrogen (ii) Ammonia (iii) Nitrogen (I) oxide
(iv) Hydrogen chloride.

A. ii and iii

B. i and iii

C. ii and iv

D. ii only

When sodium hydroxide is heated with ammonium tetraoxosulphate (IV), the gas given off may be collected by?

A. bubbling it through concentrated H₂SO₂

B. bubbling it through water and then passing it through calcium oxide

C. passing it directly through calcium oxide

D. passing it directly through calcium chloride

Which of the following elements will form oxide which will dissolve both in dilute HNO₃ and NaOH solutions to form salts?

A. Al

B. Mg

C. Ag

D. Mn