Waec Chemistry 2005 Past Questions and Answers

Question 21:

• WAEC 2005

Consider the reaction represented by the equation below, xNH_3(g) + yCI_2(g) → zHCI_(g) + N_2(g) The values of x,y and z are respectively

A. 2, 4, 6
B. 3, 2, 4
C. 2, 3, 6
D. 3, 2 6

Question 22:

• WAEC 2005

Which of the following compounds dissolves readily in water?

A. BaSO₄
B. CuSO₃
C. NH₄CI
D. AgCI

Question 23:

• WAEC 2005

When ice is changing to water, its temperature remains the same because the heart gained is

A. Used to separate the molecules
B. Lost partially to the atmosphere
C. Used to increase the volume of ice
D. Less than the activation energy

Question 24:

• WAEC 2005

Which of the following methods is suitable for preparing insoluble salts?

A. Thermal decomposition
B. Oxidation
C. Double decomposition
D. Neutralization

Question 25:

• WAEC 2005

Which of the following reactions is sulphur (IV) oxide acting agent?

A. 2HNO _3(aq) + SO_2(g) → H₂SO_4(aq) + 2NO_2(g)
B. 2KMnO _4(aq) + 5SO_2(g) + 2H₂O → K₂SO_4(aq) +MnSO_4(aq) 2H₂SO_4(aq)
C. FeCI_3(aq) + SO_2(g) + 2H₂O_(l) → FeCI _2(g)+ 2HCI_(g) + H₂SO_4(aq)
D. 2H₂S_(g) + SO_2(g) →2H₂O_(l) + 3S_(s)