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.

1,256.

Which of the following statements about volatile liquids is correct? They have

A.

high vapour pressure and low boiling point

B.

high vapour pressure and high boling point

C.

low vapour pressure and low boining point

D.

low vapour pressure and high boiling point

Correct answer is A

No explanation has been provided for this answer.

1,257.

The vapour pressure of a given volume of liquid increase when the

A.

liquid becomes saturated with a salt

B.

Volume of the liquid increases

C.

temperature of the liquid falls

D.

temperature of the Liquid rises

Correct answer is D

No explanation has been provided for this answer.

1,258.

Which of the following relationships correctly expresses the Boyle's law?

A.

P \(\alpha\) V at constant T

B.

V \(\alpha\) T at constant P

C.

P \(\alpha\) \(\frac{1}{V}\) at constant T

D.

V \(\alpha\) \(\frac{1}{T}\) at constant P

Correct answer is C

No explanation has been provided for this answer.

1,259.

Which of the following statements about a chemical system in equilibrium is correct/ The

A.

reaction is irreversible

B.

reaction goes to completion

C.

equilibrium is re-established when a stress is applied

D.

equilibrium position is affected by catalyst

Correct answer is C

No explanation has been provided for this answer.

1,260.

The mass of 800cm3 of gas Q at s.t.p. is 1.0g. What is the molar mass of Q? [Avogadros constant = 22.4dm3 mol-1`]

A.

18.0 gmol-1

B.

22,4gmol-1

C.

28.0gmol-1

D.

36.0 gmol-1

Correct answer is C

Imole Q occupies 22400 cm3
x mole occupies 800 cm3
x = \(\frac{800 x 1}{22400}\)
= 0.036mol

Molar mass = Mass ÷ Mole 

                    = 1 ÷ 0.036

 Molar mass ≈ 28 g/mol