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.

2,146.

A salt which loses mass when exposed to air is

A.

hygroscopic

B.

deliquescent

C.

efflorescent

D.

fluorescent

E.

effervescent

Correct answer is C

No explanation has been provided for this answer.

2,147.

The empirical formula of hydrocarbon containing 0. 12 mole of carbon and 0.36 mole of hydrogen is

A.

CH2

B.

CH3

C.

C2H2

D.

C2H4

E.

C2H6

Correct answer is B

No explanation has been provided for this answer.

2,148.

Given that 32.0g sulphur contains 6.02 x 10 23 sulphur atoms how many atoms are there in 2.70g of aluminium? {Al = 27, S =32}

A.

6.02 x 10 23

B.

3.01 x 1022

C.

6.02 x 1022

D.

5. 08 x 1022

E.

3.01 x 1022

Correct answer is C

27g Aluminium = \(6.02 \times 10^{23}\)

1g Al = \(\frac{6.02 \times 10^{23}}{27}\)

2.7g Al = \(\frac{6.02 \times 10^{23}}{27} \times 2.7\)

= \(6.02 \times 10^{22} Al \) atoms

2,149.

Which of the following does not affect the rate of a chemical reaction?

A.

Addition or presence of a catalyst

B.

Size of the reacting particles

C.

The enthalpy change for the reaction

D.

Concentration of the reactants

E.

Temperatureat which the reaction is carried out

Correct answer is C

No explanation has been provided for this answer.

2,150.

Which of the following compound is aromatic?

A.

Benzene

B.

Cyclobutane

C.

Cyclopentane

D.

Hexane

E.

Ethene

Correct answer is A

No explanation has been provided for this answer.