An iron beaker containing liquid X is placed on the bench in a laboratory. Liquid X begins to evaporate slowly.

1. (a)Explain why the evaporation causes the temperature of liquid X to decrease.[2]
2. (b)(i)The induction heater contains a coil of wire in which there is a high-frequency alternating current (a.c.). The alternating current in the coil generates a current in the base of the iron beaker by electromagnetic induction. Explain how electromagnetic induction generates the current in the base of the iron beaker.[3]
3. (b)(ii)The current in the base of the iron beaker causes the base to become hot. The temperature of the liquid at point P just above the base increases. Fig. 5.2 shows the position of point P. Explain, in terms of particles, why the density of liquid X decreases as its temperature increases. [Figure 5.2][3]
4. (b)(iii)The decrease in the density of the liquid at point P causes the transfer of thermal energy throughout liquid X. Explain how this happens.[2]

This question uses a diagram from the original paper, which isn't shown here. Open the full paper from the past papers archive to see it.