Post Utme Chemistry Past Questions and Answers

Question 181:

Radioisotopes are used tier the following EXCEPT

A. Development of photographic films
B. Generation of electricity
C. Radio carbon dating
D. Tracers in chemical reactions

Question 182:

The common characteristics shared by iron and aluminium is that both ____________

A. Are extracted by reduction method
B. Form only basic oxides
C. Show oxidation states of \(+2\) and \(+3\)
D. Form soluble hydroxides

Question 183:

In the reaction: \(\mathrm{H}_{3} \mathrm{C}-\mathrm{C} \equiv \mathrm{CH}+\) \(2 \mathrm{HBr} \rightarrow \mathrm{X}, \mathrm{X}\) is ____________

A. \(\mathrm{CH}_{3} \mathrm{CBr}_{2} \mathrm{CH}_{3}\)
B. \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CHBr}_{2}\)
C. \(\mathrm{CH}_{3} \mathrm{CHBrCHBr}\)
D. \(\mathrm{CH}_{2} \mathrm{BrCH} \mathrm{C}_{2} \mathrm{CH}_{2} \mathrm{Br}\)

Question 184:

The separation of oil and water with different boiling points can best be achieved by ____________

A. Fractional distillation
B. Decantation
C. Evaporation
D. Using a separating funnel

Question 185:

Calculate the minimum volume of oxygen that is required for the complete combustion of a mixture of \(20 \mathrm{~cm}^{3}\) of \(\mathrm{CO}\) and \(25 \mathrm{~cm}^{3}\) of hydrogen.

A. \(45 \mathrm{~cm}^{3}\)
B. \(22.5 \mathrm{~cm}^{3}\)
C. \(20 \mathrm{~cm}^{3}\)
D. \(10 \mathrm{~cm}^{3}\)