Post Utme Chemistry Past Questions and Answers

Question 706:

The removal of rust from iron by treatment with tetraoxosulphate (VI) acid is based on the ____________

A. Hydrolysis of the iron
B. Reaction of acid with base
C. Oxidation of the rust
D. Dehydration of the iron

Question 707:

Which of the following constitutes a mixture?
I. Petroleum
II. Rubber Latex
III. Vulcanizers solution
IV. Carbon (II) sulphides

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

Question 708:

\(30 \mathrm{~cm}^{3}\) of oxygen at 10 atmosphere pressure is places in a \(20 \mathrm{dm}^{3}\) container. Calculate the new pressure if temperature is kept constant.

A. \(6.7 \mathrm{~atm}\)
B. \(15.0 \mathrm{~atm}\)
C. \(6.0 \mathrm{~atm}\)
D. \(66.0 \mathrm{~atm}\)

Question 709:

A sample of gas exerts a pressure of \(8.2\) atm when confined in a \(2.93 \mathrm{dm}^{3}\) container at \(20^{\circ} \mathrm{C}\). The number of moles of gas in the sample is ____________

A. \(1.00\)
B. \(2.00\)
C. \(3.00\)
D. \(4.00\)

Question 710:

A quantity of air was passed through a weighted mount of alkaline pyrogallol. An increase in weight of the pyrogallol would result from the absorption of ____________

A. Nitrogen
B. Neon
C. Argon
D. Oxygen