Post Utme Chemistry Past Questions and Answers

Question 446:

Which of the following acts as both a reducing and oxidizing agent?

A. \(\mathrm{H}_{2}\)
B. \(\mathrm{SO}_{2}\)
C. \(\mathrm{H}_{2} \mathrm{~S}\)
D. \(\mathrm{CO}_{2}\)

Question 447:

Which of the following is not a unit of temperature?

A. \({ }^{\circ} \mathrm{C}\)
B. \({ }^{\circ} \mathrm{F}\)
C. \(\mathrm{K}\)
D. \({ }^{\circ} \mathrm{K}\)

Question 448:

Which of the following statement is true of \(\Delta \mathrm{H}\), the enthalpy of reaction? It is ____________

A. The heat of change accompanying a chemical change
B. Negative for exothermic reactions
C. Positive for endothermic reactions
D. All of the above

Question 449:

A saturated solution of potassium chloride was prepared at \(X^{\circ} \mathrm{C}\). If \(30 \mathrm{~m}^{3}\) of this solution required \(22.5 \mathrm{~cm}^{3}\) of silver trioxonitrate (V) solution, containing \(34 \mathrm{~g}\) in \(100 \mathrm{~cm}^{3}\) solution for complete precipitation. Calculate the solubility of potassium chloride at \(\mathrm{X}^{\circ} \mathrm{C}\) in moldm \({ }^{-1} \quad\) (take \(\mathrm{KCl}=74.5\), \(\left.\mathrm{AgNO}_{3}=170 \right)\)

A. \(1.5 \mathrm{moldm}^{-3}\)
B. \(2.0 \mathrm{moldm}^{-3}\)
C. \(0.15 \mathrm{moldm}^{-3}\)
D. \(0.20\) moldm \({ }^{-3}\)

Question 450:

The general methods of preparing salts include
I. Neutralization
II. Precipitation
III. Double decomposition
IV. Action of an acid on a metal

A. I and II
B. III and II
C. II and III
D. I, II, III and IV