Chemistry questions and answers

Chemistry Questions and Answers

Learn more about the properties, composition, and structure of substances (elements and compounds) with these Chemistry questions and answers. This Test can be used by students preparing for Chemistry in JAMB, WAEC, NECO or Post UTME.

891.

The pollutant that contributes to the depletion of the ozone layer is

A.

CFCs

B.

NO2

C.

SO2

D.

CO

Correct answer is A

No explanation has been provided for this answer.

892.

The compound produced when sodium peroxide is heated with excess sodium is

A.

Na2CO3

B.

Na2O

C.

NaNO2

D.

NaOH

Correct answer is B

No explanation has been provided for this answer.

893.

The radioisotope used in industrial radiography for the rapid checking of faults in welds and casting is

A.

Phosphorus-32

B.

Cobalt-60

C.

Carbon-14

D.

Iodine-131

Correct answer is B

No explanation has been provided for this answer.

894.

What is the concentration of a solution containing 2g of NaOH in 100cm3 of solution?
[Na=23, O=16, H=1]

A.

0.05 moldm-3

B.

0.30 moldm-3

C.

0.50 moldm-3

D.

0.40 moldm-3

Correct answer is C

2g NaOH is contained in 100cm3
Xg NaOH is contained in 1000cm3

Xgram = \(\frac{2\times 1000}{100}\) = 20g

Mole = \(\frac{20}{40}\) = 0.50mol/dm3

895.

The process that requires the use of hardwater in its operation is

A.

Tanning

B.

Bottling

C.

Laundry

D.

Dyeing

Correct answer is B

No explanation has been provided for this answer.