Post Utme University of Nigeria Chemistry Past Questions and Answers

Question 6:

Sodium hydroxide should be stored in properly closed containers because it ____________

A. Readily absorbs water vapour from the air
B. Is easily oxidized atmospheric oxygen
C. Turns golden yellow when exposed to light
D. Melts at low temperature

Question 7:

\(2 \mathrm{H}_{2} \mathrm{~S}_{(\mathrm{g})}+\mathrm{SO}_{2(\mathrm{~g})}
ightarrow 3 \mathrm{~S}_{(\mathrm{g})}+\) \(2 \mathrm{H}_{2} \mathrm{O}_{(1)}\).

The above reaction is ____________

A. A redox reaction in which \(\mathrm{H}_{2} \mathrm{~S}\) is the oxidant and \(\mathrm{SO}_{2}\) is the reductant
B. A redox reaction in which \(\mathrm{SO}_{2}\) is the oxidant and \(\mathrm{H}_{2} \mathrm{~S}\) is the reductant
C. Not a redox reaction because there is no oxidant in the reaction equation
D. Not a redox reaction because there is no reductant in the reaction equation

Question 8:

How many unpaired electrons are in the p-orbitals of a fluorine atom?

A. 1
B. 2
C. 3
D. O

Question 9:

A metal \(M\) displaces zinc from \(\mathrm{ZnCl}_{2}\) solution. This shows that ____________

A. Electrons flow from zinc to \(M\)
B. \(M\) is more electropositive than zinc
C. \(M\) is more electronegative than zinc
D. Zinc is more electropositive than M

Question 10:

Which of the following relationships between the pressure \(P\), the volume \(V\) and the temperature \(\mathrm{T}\), represents an ideal gas behaviour?

A. \(P \propto V T\)
B. \(P \propto\)
C. \(P V \propto 1\)
D. \(\mathrm{PT} \propto \mathrm{V}\)