Waec Chemistry 1997 Past Questions and Answers

Question 11:

• WAEC 1997

A given volume of methane diffuses in 20 seconds. How long will it take the same volume of sulphur (IV) oxide to diffuse under the same conditions? [CH4 = 16; SO2 = 64]

A. 5 seconds
B. 20 seconds
C. 40 seconds
D. 60 seconds
E. 80 seconds

Question 12:

• WAEC 1997

An acid is a substance which in the presence of water produces

A. Salts
B. Oxygen
C. Effervescence
D. Hydroxonium ions
E. Hydrogen gas

Question 13:

• WAEC 1997

Which of the following is a general method of preparing acids?

A. Direct combination of constituent elements
B. Double decomposition involving a salt solution
C. Reaction between an anhydride and water
D. Reaction between a base and an amphoteric oxide
E. Dissolution of hydroxides followed by neutralization

Question 14:

• WAEC 1997

Which of the following is a general method of preparing acids?

A. Direct combination of constituent elements
B. Reaction between a base and an amphoteric oxide
C. Double decomposition involving a salt solution
D. Reaction between an anhydride and water
E. Dissolution of hydroxides followed by neutralization

Question 15:

• WAEC 1997

The loss of molecules of water of crystallization to the atmosphere by some crystalline salts is known as

A. Efflorescence
B. Effervescence
C. Phosphorescence
D. Fluorescence
E. Deliquescence