Thermal Properties

A substance loses thermal energy (heat) to the surroundings at a steady rate. The graph shows how the temperature of the substance changes with time.

What could the portion PQ of the graph represent?

• gas condensing

• gas cooling

• liquid cooling

• liquid solidifying

A student wishes to check the upper and the lower fixed points on a Celsius scale thermometer.

She has four beakers P, Q, R and S.

Which two beakers should she use to check the fixed points?

• P and R

• P and S

• Q and R

• Q and S

The same quantity of thermal energy is supplied to two solid objects X and Y.

The temperature increase of object X is greater than the temperature increase of object Y.

Which statement explains this?

• X has a lower melting point than Y.

• X has a lower density than Y.

• X has a lower thermal capacity than Y.

• X is a better thermal conductor than Y.

Which statement describes what happens as ice at 0°C starts to melt to become water?

• Energy is absorbed and the temperature remains constant.

• Energy is absorbed and the temperature rises.

• Energy is released and the temperature remains constant.

• Energy is released and the temperature rises.

What is meant by the fixed points of the scale of a liquid-in-glass thermometer?

• the distance between one scale division and the next

• the highest and lowest temperatures that the thermometer can record

• the maximum and minimum depth to which the thermometer should be submerged in a liquid

• the two agreed temperatures used for marking the temperature scale

A liquid at room temperature fills a flask and a glass tube to level X.

The flask is now placed in ice, and the liquid level in the tube falls to level Y.

Why does the level fall?

• The flask contracts.

• The flask expands

• The liquid contracts.

• The liquid expands.

The melting points of ethanol and mercury are shown.

Which of these two liquids is / are suitable to use in a liquid-in-glass thermometer to measure temperatures of –50°C and –120°C?

• ethanol only

• ethanol and mercury

• mercury only

• neither ethanol nor mercury

Which quantity gives the thermal capacity of a beaker?

• the thermal energy required to change the state of the beaker at constant temperature

• the thermal energy required to raise the temperature of the beaker by 1°C

• the total mass of hot liquid that the beaker can hold

• the total volume of hot liquid that the beaker can hold

A jug of water is at room temperature. Several ice cubes at a temperature of 0°C are dropped into the water and they begin to melt immediately. What happens to the temperature of the water and what happens to the temperature of the ice cubes while they are melting?

• A

• B

• C

• D

Which quantity gives the thermal capacity of a beaker?

• the thermal energy required to change the state of the beaker at constant temperature

• the thermal energy required to raise the temperature of the beaker by 1°C

• the total mass of hot liquid that the beaker can hold

• the total volume of hot liquid that the beaker can hold