Chemistry Past Questions and Answers

(a) Give the products of the following reactions:
(i) hydrolysis of simple proteins.
(ii) alkaline hydrolysis of fats and oils.

(b) A combustion tube was packed with small pieces of broken clay pot and the tube maintained at a temperature of 750K. When the vapour of decane was passed into the tube, the main products included a gaseous hydrocarbon X.
(i) Name the process involved in the reaction. Give its industrial application.
(ii) State the function of the pieces of broken pot in the experiment.
(iii) Give one chemical test to distinguish between X and methane.
(iv) Draw a labelled diagram for the laboratory preparation of X.

(c)(i) State what would be observed if a piece of sodium was added to 10cm\(^3\) of propanol in a beaker. Write an equation for the reaction.
(ii) Give the main product formed when excess acidified potassium heptaoxodichromate (VI) reacts with each of the following: propan-1- ol: propan - 2 -of; State the type of process involved in the reactions.

(a)(i) State Graham's law of diffusion.
(ii) Consider the reaction represented by the following equation:
N\(_2\)O\(_{4(g)}\) 2NO\(_{2(g)}\)
Night yellow dark brown
State what would happen to the vapour density of N\(_2\)O\(_4\) as the temperature of the system is increased. If the system is cooled, would the gases become lighter or darker in colour? Explain your answer in each case.

(b) Explain the following observations:
(i) an inflated balloon that was left in the sun. burst after some time;
(ii) a pure sample of a liquid did not have a constant boiling point at the top and at the base of a high mountain

(c)(i) List two gaseous reducing agents
(ii) Write one equation each to illustrate the reducing property of the gases you listed in (c)(i) above.

Copper metal will react with concentrated trioxonitrate (V) acid to give?

Copper metal will react with concentrated trioxonitrate (V) acid to give?

Which of the following separation is routinely applied in the petroleum industry