Post Utme University of Nigeria Chemistry Past Questions and Answers

Question 11:

Increasing the pressure of a gas, ____________

A. Lowers the average kinetic energy of the molecules
B. Decreases the density of the gas
C. Decreases the temperature of the gas
D. Increases the density of the gas

Question 12:

A quantity of electricity liberates \(3.6 \mathrm{~g}\) of silver from its salt. What mass of aluminium will be liberated from its salt by the same quantity of electricity?

A. 2.7g
B. 1.2 g
C. 0.9 g
D. 0.3 g

Question 13:

The Avogadro's number of \(24 \mathrm{~g}\) of magnesium is the same as that of ____________

A. \(1 \mathrm{~g}\) of hydrogen molecules
B. \(16 \mathrm{~g}\) of oxygen molecules
C. \(32 \mathrm{~g}\) of oxygen molecules
D. \(35.5 \mathrm{~g}\) of chlorine molecules

Question 14:

Which of the following is arranged in order of increasing electronegativity?

A. Chlorine, aluminium, magnesium, phosphorus, sodium
B. Sodium, magnesium, aluminium, phosphorus, chlorine
C. Chlorine, phosphorus, aluminium, magnesium, sodium
D. Sodium, chlorine, phosphorus, magnesium, aluminium

Question 15:

Fluorine does not occur in the free state in nature because ____________

A. It is inert
B. Of its high reactivity
C. It is a poisonous gas
D. It belongs to the halogen family