JAMB Past Questions and Answers - Page 1423

7,111.

Which of the following compounds can be represented by the molecular formula C2 H6O?

A.

propanal

B.

ethanol

C.

methanoic acid

D.

glucose

Correct answer is B

Ethanol has the molecular formula C2H6O. Option A, C, D are not because their molecular are not different

7,112.

If glucose is heated with concentrated tetraoxosulphate(vi)acid, it will be dehydrated to?

A.

carbon

B.

carbon(iv)oxide

C.

ethane

D.

ethanol

Correct answer is A

Carbon concentration of 4 will not give a precipitate heating. Option B,C,D will not be dehydrated

7,113.

The substance that is used in the steel industry for the removal of carbon. Sulphur and phosphorus impurities from pig iron is

A.

oxygen

B.

chlorine

C.

nitrogen

D.

hydrogen

Correct answer is A

Oxygen is a substance that is used to remove impurities from pig iron. Options B, C, D will be effective in removing impurities positive]

7,114.

In countries where the temperature fall below 273k, salt always spilled on the road in order to

A.

increase the boiling point

B.

increase the density of the ice

C.

make the ice impure

D.

reduce the freezing point of ice

Correct answer is D

No explanation has been provided for this answer.

7,115.

Electronic configuration of an element 13 in the subsidiary energy level is

A.

\( 1s^2 2s^2 2p^6 3s^2 3p^1 \)

B.

\( 1s^22s^2 2p^4 3p^1 3s^1 \)

C.

\( 1s^2 2s^2 2p^6 3s^2 3p^3 \)

D.

\( 1s^1 2s^2 2p^6 3s^2 3p^4 \)

Correct answer is A

No explanation has been provided for this answer.