Change of State - Jamb Physics Past Questions and Answers

Question 46:

• JAMB 2015

Which of the following will increases the boiling point of water?
I. Taking it to a high altitude
II. Dissolving a salt into it
III. Heating it in a sealed flask
IV. Increasing the rate of heat supply
.

A. I only
B. III & IV only
C. II & III only
D. II only

Question 47:

• JAMB 2015

Volatile liquids usually

A. Have high boiling points
B. Have low boiling points
C. Have high densities
D. Have high melting points

Question 48:

• JAMB 2016

The rate of cooling of a heated quantity of liquid in an enclosure depends on the

A. Pressure of the liquid
B. Temperature in the enclosure
C. Pressure of the enclosure
D. Volume of the liquid

Question 49:

• JAMB 2016

Boiling occurs when the vapour pressure of a liquid is

A. At the evaporation point
B. Less than the atmospheric pressure
C. Greater than the atmospheric pressure
D. Equal to the atmospheric pressure

Question 50:

• JAMB 2017

Calculate the specific latent heat of vaporization of steam of 1.13 x 106J of heat energy is required to convert 15kg of steam to water.

A. 7.53 x 105 Jkg\(^{-1}\)
B. 7.53 x 10-2Jkg\(^{-1}\)
C. \(7.53 \times 10^{4}\)Jkg\(^{-1}\)
D. 7.53 x 10-3Jkg\(^{-1}\)