(a)[2]
A liquid takes up a far smaller volume than a gas containing the same number of molecules. Explain why this happens.
(b(i))[1]
State the equation that connects $V_1$, $V_2$, $p_1$ and $p_2$.
(b(ii))[3]
The gas in the cylinder starts at a pressure of $1.2 \times 10^5\,\text{Pa}$ and an initial volume of $100\,\text{cm}^3$. The piston has a cross-sectional area of $5.0\,\text{cm}^2$ and is driven in by $8.0\,\text{cm}$. Calculate the pressure of the gas after compression.
(b(iii))[1]
Explain why the pressure of the gas changes, using ideas about molecules.