Waec Chemistry 1995 Past Questions and Answers

Question 31:

• WAEC 1995

(a) State three reasons why air is classified as a mixture.
(b) List two methods that can be used to separate a mixture of iodine crystals and iron filings.

Question 32:

• WAEC 1995

What name is given to each of the following? The
(a) irregular random movement of smoke particles in air.
(b) existence of an element in various forms in the same physical-state
(c) disintegration of atomic nuclei, accompanied with radiation emission.
(d) conversion of a solid difitrunto vapour without melting.

Question 33:

• WAEC 1995

(a)(i) Explain the term pH
(ii) If sodium hydroxide solution were added to a solution of a strong acid, what would happen to the pH of the solution?

(b) Give one example of each of the following:
(i) acidic oxide
(ii) acid salt.

Question 34:

• WAEC 1995

(a)(i) Sketch a graph to illustrate Charles' law.
(ii) A gas occupies 500 cm\(^{ 3}\) at 2TC. calculate its volume at 40°C constant pressure.

(b) List two gases that are used as refrigerant

Question 35:

• WAEC 1995

(a) State the type of reaction involved in the conversion of:
(i) proteins.to amino acids:
(ii) ethanol to ethene;
(iii) benzene to bromobenzene

(b) Write an equation to show that ethene reasts with hydrogen in the presence of finely divided nickel.