Waec Chemistry 2002 Past Questions and Answers

Question 21:

• WAEC 2002

Which of the following decreases when a given mass of gas is compressed to half its initial volume?

A. Average intermolecular distance
B. Frequency of collisions
C. Number of molecules present
D. Atomic radius of each particle

Question 22:

• WAEC 2002

What volume of hydrogen will be produced if 100cm³ of ammonia is completely decomposed at constant temperature and pressure? The equation for reaction is 2NH_3(g) → N_2(g) + 3H_2(g)

A. 50cm³
B. 150cm³
C. 200cm³
D. 300cm³

Question 23:

• WAEC 2002

Calculate the mass of chlorine gas which occupies a volume of 1.12 dm\(^3\) a volume of 1.12 dm\(^3\) at s.t.p [Cl = 35.5, 1 mole og gas occupies 22.4 dm\(^3\) at s. t. p ]

A. 1.80g
B. 3.55g
C. 7.10g
D. 15.50g

Question 24:

• WAEC 2002

Determine the mass of sulphur (IV) oxide obtained when 91.0g of oxygen reacts completely with sulphur according to the following equation: S_(s) + O_2(g) → SO_2(g) [S = 32; O = 16]

A. 123g
B. 139g
C. 155g
D. 182g

Question 25:

• WAEC 2002

The gas given off when NH₄ Cl is heated with an alkali is

A. H₂
B. Cl₂
C. N₂
D. NH₃