A student investigates how the pressure of a fixed mass of gas changes with temperature at a constant volume.
The graph shows her results.
Extend the line of best fit to find the temperature of the gas when the pressure is zero kPa\text{kPa}kPa.
State what happens to the average kinetic energy of the gas molecules when the temperature of the gas is decreased.
The student then investigates how the volume of a gas changes with temperature at a constant pressure.
State two variables that she should control in this investigation.
Describe the relationship between the volume of a gas and its temperature (in kelvin). You may sketch a graph to help your answer.
