Question 606:

• JAMB 1989

Mortar is NOT used for under-water construction because

A. It hardens by lose of water
B. Its hardening doe not depend upon evaporation
C. It requires concrete to harden
D. It will be washed away by the flow of water

Question 607:

• JAMB 1989

Which of the following is NOT involved in the extraction of metals from their ores?

A. Reduction with carbon
B. Reduction with other metals
C. Reduction by electrolysis
D. Oxidation with oxidizing agents

Question 608:

• JAMB 1989

When excess chlorine is mixed with ethene at room temperature, the product is

A. 1,2 - dichloroethane
B. 1,2 - dichloroethene
C. 1,1 - dichloroethane
D. 1, 1 - dichloroethene

Question 609:

• JAMB 1989

Vulcanization of rubber is a process by which

A. Isoprene units are joined to produce rubber
B. Rubber latex is coagulated
C. Sulphur is chemically combined in the rubber
D. Water is removed from the rubber

Question 610:

• JAMB 1989

The reaction between ethanoic acid and sodium hydroxide is an example of

A. Esterification
B. Neutralization
C. Hydroxylation
D. Hydrolysis