Suggest why the times for the temperature to fall from $20^\circ\text{C}$ to $10^\circ\text{C}$ and from $0^\circ\text{C}$ to $-10^\circ\text{C}$ are not the same.
Explain what happens to the molecules of the oil and what happens to the level of the oil in the glass measuring cylinder as the temperature drops from $20^\circ\text{C}$ to $0^\circ\text{C}$.
Determine the temperature at which the oil melts.
Explain, in terms of molecules, why the temperature of the oil stays the same between $t = 3600\,\text{s}$ and $t = 10800\,\text{s}$.
Calculate the energy transferred from the oil between $t = 3600\,\text{s}$ and $t = 10800\,\text{s}$. The mass of oil is $45\,\text{g}$ and the specific latent heat of fusion is $5.7 \times 10^{4}\,\text{J kg}^{-1}$.
Calculate the average rate at which energy is transferred from the oil between $t = 3600\,\text{s}$ and $t = 10800\,\text{s}$.
Use the graph in Fig. 9.1 to compare the specific heat capacity of oil in the liquid and solid states and explain how you know.