Question 1
Paper 2Hard8 marksA sample of ice is heated at constant pressure. Figure 1 shows the structural formula of the substance. The temperature is recorded at intervals.
| Time / min | Temperature / °C |
|---|---|
| 0.0 | −8.2 |
| 2.0 | −2.1 |
| 4.0 | 0.0 |
| 6.0 | 0.0 |
| 8.0 | 8.1 |
| 10.0 | 32.2 |
(a)[1]
State the formula of each particle in the sample, using Figure 1.
(b)[2]
Convert the temperatures recorded at 8.0 min and 10.0 min to kelvin, to the nearest kelvin.
(c)[1]
Identify the time interval during which the sample is changing state.
(d)[4]
A student concludes: “At 10.0 min, the average kinetic energy of the particles is about four times its value at 8.0 min, because 32.2 is about four times 8.1. The average kinetic energy also continues to increase from 4.0 to 6.0 min because the sample is still being heated.”
Evaluate both statements, using the data and your answer to (b).