Waec Chemistry 1992 Past Questions and Answers

Question 6:

• WAEC 1992

Which of the following processes is a physical reaction?

A. Electrolysis
B. Hydrolysis
C. Allotropic change
D. Neutralization
E. Corrosion

Question 7:

• WAEC 1992

If the volume of a given mass of gas at 298 K and pressure of 205.2 x 10³ Nm-² is 2.12dm³, what is volume of the gas at s.t.p? (Standard pressure = 101.3 x 10³ Nm-₂, Standard temperature = 273K)

A. 39.3dm ³
B. 22.4dm³
C. 4.93dm³
D. 3.93dm³
E. 0.393dm³

Question 8:

• WAEC 1992

The following acids are monobasic except

A. Methanoic acid
B. Dioxonitrate lll acid
C. Ethanedioic acid
D. Oxochlorate (l) acid
E. Hydrobromic acid

Question 9:

• WAEC 1992

The reactions ethyne are mainly

A. Substitution reactions
B. Addition reactions
C. Addition polymerization
D. Catalytic hydrogenation
E. Catalytic halogenation

Question 10:

• WAEC 1992

When air is passed through potash and then pyrogallol, the components are noble gases,

A. Oxygen and carbon (IV) oxide
B. Oxygen and nitrogen
C. Nitrogen and water vapour
D. Water vapour and carbon (IV) oxide
E. Oxygen and water vapour