WAEC Past Questions and Answers - Page 3275

16,371.

Which of the following factors decreases the rate of evaporation of a liquid?

A.

increase in pressure over the liquid

B.

lowering the boiling point

C.

decreasing in humidity

D.

wind

Correct answer is A

No explanation has been provided for this answer.

16,372.

A piece of copper of mass 20g at a temperature of 110°C was dropped into a mixture of ice and water at 0°C. If the final steady temperature of the mixture is 0°C . Calculate the amount of ice that melted [Specific heat capacity of copper = 0.4 Jg\(^{-1}\)K\(^{-1}\), specific latent heat of fusion of ice = 330Jg\(^{-1}\)]

A.

0.37g

B.

0.60g

C.

2.40g

D.

2.70g

Correct answer is D

Mice = \(\frac{MC}{\theta}\)

= \(\frac{20 \times 0.4 \times 110}{330} 

Heat lost by copper = Heat gained by ice

m\(_{copper}\) c \(\theta\) = m\(_{ice}\) L

20 x 0.4 x (110 - 0) = m\(_{ice}\) x 330

m\(_{ice}\) = \(\frac{20 \times 0.4 \times 110}{330}\)

= \(\frac{8}{3}\)

= 2.67 g

= 2.70g (to 1 d.p)

16,373.

The financial institution that specializes in risk spreading is called

A.

An investment bank

B.

A development bank

C.

An insurance company

D.

The stockexchange

Correct answer is C

Insurance company is a financial institution that provides coverage, in the form of compensation resulting from loss, damages, injury, treatment or hardship to personal and business assets.

16,374.

In the formation of sea breeze. wind blows from

A.

sky to land

B.

sea to sky

C.

land to sea

D.

sea to land

Correct answer is D

A sea breeze describes a wind that blows from the ocean (sea) inland towards land.

16,375.

All of the following is the features of optimum population except

A.

Full employment of available resources

B.

Unlimited amount of unexploited resources

C.

Maximum per capita production and income

D.

High standard of living

Correct answer is B

Optimum population yields highest quality of life, which means each person has access to adequate food, water, energy and air of highest quality, adequate medical care, recreational facilities and cultural outlets. It does not include unlimited amount of unexploited resources.