Nov 2012 [32] Q (2) 2 chem
The diagram shows a heating curve for a sample of compound X. F 80 E temperature/C 2 00 15 с S A time (a) Is X a solid, a liquid or a gas at room temperature, 20 °C? ...liquid... [1] (b) Write an equation for the equilibrium which exists in region BC. [2] (c) Name the change of state which occurs in region DE. [1] (d) Explain how the curve shows that a pure sample of compound X was used. * [2]​