JAMB Chemistry Past Questions & Answers - Page 87

431.

An isotope has an atomic number of 15 and a mass number of 31. The number of proton it contains is

A.

16

B.

15

C.

31

D.

46

Correct answer is B

No explanation has been provided for this answer.

432.

An example of a solid emulsion is

A.

Butter

B.

Hair cream

C.

Milk

D.

Cod-liver oil

Correct answer is A

No explanation has been provided for this answer.

433.

In a neutralization reaction involving HCI and NaOH using litmus as indicator, the colour at the end point is

A.

Blue

B.

Red

C.

Orange

D.

Purple

Correct answer is D

Neutral litmus paper is purple.  the result of a neutralization reaction is salt and water and hence is neutral.

434.

In the extraction of iron, the waste gas from the furnace is a mixture of

A.

PH3 CO and CO2

B.

CO and C

C.

N2 , CO and CO2

D.

PH3 and CO

Correct answer is C

the \(N_2\) from the hot air blast to burn the coke (48%), the \(CO\) (23%) and \(CO_2\) (21%) produced from the reduction of the iron ore \(Fe_{2}O_{3}\) by carbon (the coke) are the major components of the waste from the extraction.

435.

The arrangement of particles in crystal lattices can be studied using

A.

X-rays

B.

\(\beta\)-rays

C.

\(\alpha\)-rays

D.

\(\gamma\)-rays

Correct answer is A

No explanation has been provided for this answer.