WAEC Chemistry Past Questions & Answers - Page 86

426.

The general gas equation \(\frac{PV}{T}\) = K is a combination of

A.

Boyle's and Charles' laws

B.

Boyle's and Graham's laws

C.

Charles' and Graham's laws

D.

Dalton's and Graham's laws

Correct answer is A

No explanation has been provided for this answer.

427.

Which of the following apparatus can be used to measure a specific volume of a liquid accurately?

A.

Beaker

B.

Conical flask

C.

Measuring cyclinder

D.

Pipette

Correct answer is D

No explanation has been provided for this answer.

428.

Which of the following statements about solids is correct?

A.

Solid particles are less orderly than those of a liquid

B.

Solid have lower densities than liquids

C.

Solid particles have greater kinetic energies than those of liquids

D.

Solid particles cannot be easily compressed

Correct answer is D

No explanation has been provided for this answer.

429.

How many moles of oxygen would contain 1.204 x 1024 molecules?
[Avogadro's constant (NA) = 6.02 x 1023]

A.

1

B.

2

C.

3

D.

4

Correct answer is B

6.02 x 1023 molecules is 1mole
1.204 x 1024 molecules will be......

\(\frac{1.204 \times 10^24 \times 1}{6.02 \times 10^23}\)

\(\frac{1.204 \times 10}{6.02}\) = \(\frac{12.04}{6.02}\) = 2moles

430.

An element X froms the following oxides X2O, XO and XO2. This phenomenon illustrates the law of________?

A.

Conservation of mass

B.

Definite proportion

C.

Mass action

D.

Multiple proportion

Correct answer is D

No explanation has been provided for this answer.