JAMB Chemistry Past Questions & Answers - Page 338

1,686.

The salt formed from a reaction between citric acid and sodium hydroxide in solution will be?

A.

acidic

B.

basic

C.

complex

D.

neutral

Correct answer is B

Citric acid has 3 carboxyl groups, therefore, when reacts with NaOH, there is a simple salification reaction that will produce the trisodium citrate / sodium citrate. Trisodium citrate is a tribasic salt of citric acid. It is produced by complete neutralization of citric acid with high purity sodium hydroxide or carbonate and subsequent crystallization and dehydration.

1,687.

What volume of 1.5M solution of KOH would contain 0.045 moles

A.

67.50 cm3

B.

30.00 cm3

C.

6.75 cm3

D.

3.00 cm3

Correct answer is B

No explanation has been provided for this answer.

1,688.

The acid used in electrolysis of water is dilute?

A.

HNO3

B.

CH3COOH

C.

H2SO4

D.

HCl

Correct answer is C

The electrolyte is dilute sulfuric acid (= acidified water) which, during electrolysis is split into hydrogen and oxygen gases.

1,689.

The major source of oxides of nitrogen is from the burning of

A.

coal

B.

wood

C.

fuel

D.

chlrofluorocarbons

Correct answer is C

Nitrogen oxides form when fuel is burned at high temperatures

1,690.

For a given solute, the concentration of its saturated solution in different solvents are

A.

the same at the same temperature

B.

different at the same temperature

C.

the same at different temperature

D.

constant

Correct answer is B

No explanation has been provided for this answer.