Hexene reacts with hydrogen gas to produce hexane. reaction 1 C6H12(I) + H2(g) → C6H14(I) Fig. 3.1 shows the distribution of energies of H2(g) molecules at temperature T. [Figure 3.1]

1. (a)(i)Sketch on Fig. 3.1 the shape of the curve for the same sample of H2(g) molecules when the temperature is increased.[2]
2. (a)(ii)Explain why increasing the temperature increases the rate of reaction 1.[2]
3. (a)(iii)State the role of nickel when it is added to reaction 1.[1]
4. (a)(iv)Annotate Fig. 3.2 to show the effect of adding nickel to reaction 1 at temperature T. [Figure 3.2][1]
5. (b)Define Le Chatelier's principle.[2]
6. (c)Reaction 2 shows the equilibrium reaction between X(g) and Y(g) to produce Z(g) in a sealed container. reaction 2 aX(g) + bY(g) ⇌ cZ(g) Fig. 3.3 shows the effect of changing pressure on the percentage yield of Z(g) at two different temperatures, 300K and 350K. [Figure 3.3] Deduce two conclusions about reaction 2 using Fig 3.3.[2]

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