JAMB Chemistry Past Questions & Answers - Page 212

1,057.

Which of the following statement is false?

A.

Acids react with some metals, liberating hydrogen

B.

Acids react with carbonates, liberating carbondioxide

C.

Acids conduct electricity and are decomposed by the current, liberating hydrogen at the anode

D.

Acids have a sour taste

E.

Acids change the colour of indicators

Correct answer is C

Thus, with a dilute solution of sulphuric acid and platinum electrodes, hydrogen gas is evolved at the cathode

1,058.

If one of the following oxides is heated with hydrogen or carbon using a bunsen burner, it is not reduced to the metal. Which one is it?

A.

Lead oxide

B.

Magnesium oxide

C.

Copper oxide

D.

Tin oxide

E.

Iron oxide

Correct answer is B

No explanation has been provided for this answer.

1,059.

Cellulose and starches can be classified as one of the following?

A.

sugars

B.

sucrose

C.

hydrocarbons

D.

carbohydrates

E.

isomers

Correct answer is D

No explanation has been provided for this answer.

1,060.

The best way of collecting chlorine is?

A.

by downward displacement of air

B.

by upward displacement of air

C.

over water

D.

under water

E.

over mercury

Correct answer is B

Chlorine gas is 2.5 times denser than air, hence it is best collected by the downward delivery or upward displacement of air.