Topic 3 Thermal Physics: Quiz 2 Modelling a Gas

The graph shows the distribution of speeds for the molecules of a gas at a particular temperature. Which statement is correct?

A gas is enclosed inside a cylinder which is fitted with a frictionless piston. Initially, the gas has a volume V1 and is in equilibrium with an external pressure p. The gas is then heated slowly so that it expands, pushing the piston back until the volume of the gas has increased to V2. How much work is done by the gas during this expansion?

If the Universe was such that the speed of the molecules in a substance increased with temperature but at any particular temperature the speed of all the molecules in a substance was the same, which process would not occur?

Which process does not require energy to be supplied?

A gas is enclosed in a container of fixed volume. It gains heat energy from an external source. What happens to the molecules of the gas?

A hot liquid is allowed to cool. The graph shows the cooling curve. In which part of the curve is latent heat released?

The molar mass of magnesium is 24 g. 12 g of magnesium contains the same number of particles as:

A fixed mass of an ideal gas is at temperature T. The pressure is doubled and the volume is halved. What is the temperature after these changes?

Ice at –10 °C is heated at a constant rate until it is water at +10 °C. Which graph shows how the temperature changes with time?

Which of the following is NOT an ideal gas assumption?

At regular intervals along a railway line there is a gap between the rail sections. What is the reason for the gap between the rail sections?

Ice is taken from a freezer and left in a room. The ice melts and eventually the water reaches room temperature. Which energy transfers take place?

Some air is trapped inside a small balloon. The average kinetic energy of the air molecules in the balloon is increased. What remains the same?

A clinical thermometer is designed to respond quickly to a change in temperature and to have a high sensitivity. Which design features should the clinical thermometer have?

The energy required to change liquid water into water vapour at the same temperature is called latent heat of vaporisation. What does this energy do?

A 2 kW kettle containing boiling water is placed on a balance. It is left there and continues to boil for 5 minutes. The balance reading changes by 0.2 kg. What does this information give as a value for the specific latent heat of vaporisation of water?