Post Utme Chemistry Past Questions and Answers

Question 226:

Which of the following is arranged in order of increasing atomic radius?

A. \(\mathrm{Cl}, \mathrm{P}, \mathrm{Al}, \mathrm{Mg}, \mathrm{Na}, \mathrm{Si}\)
B. \(\mathrm{Na}, \mathrm{Mg}, \mathrm{Al}, \mathrm{Si}, \mathrm{P}, \mathrm{Cl}\)
C. \(\mathrm{Cl}, \mathrm{P}, \mathrm{Si}, \mathrm{Al}, \mathrm{Mg}, \mathrm{Na}\)
D. \(\mathrm{Na}, \mathrm{Al}, \mathrm{Si}, \mathrm{Mg}, \mathrm{P}, \mathrm{Cl}\)

Question 227:

Calculate the molecular formula} of a hydrocarbon with molar mass 26 and \(92.3 \%\) of Carbon.

A. \(\mathrm{C}_{2} \mathrm{H}_{2}\)
B. \(\mathrm{C}_{3} \mathrm{H}_{3}\)
C. \(\mathrm{C}_{2} \mathrm{H}_{6}\)
D. \(\mathrm{C}_{2} \mathrm{H}_{4}\)

Question 228:

Which of these can be used in removing oil stains?

A. Benzene.
B. Chlorine water
C. Washing soda/soda ash
D. Potassium trioxonitrate \(\mathrm{V}\)

Question 229:

The position of equilibrium in a reversible reaction is affected by ____________

A. Surface area of the reactants exposed
B. Presence of catalyst
C. Changes in size of reaction flask
D. Changes in concentration of the reaction

Question 230:

Which of the following solutions containing only hydroxyl ions will liberate, hydrogen gas when reacted with magnesium metal?

A. \(1.0 \times 10^{-12} \mathrm{~mol} \mathrm{dm}^{-3}\)
B. \(1.0 \times 10^{-6} \mathrm{~mol} \mathrm{} \mathrm{dm}^{-3}\)
C. \(1.0 \times 10^{-4} \mathrm{~mol} \mathrm{dm}^{-3}\)
D. \(1.0 \times 10^{-2} \mathrm{~mol} \mathrm{} \mathrm{dm}^{-3}\)