The rate of chemical reactions is affected by changes in temperature and pressure.

1. (a)(i)Draw a curve on the axes to show the Boltzmann distribution of energy of particles in a sample of gaseous krypton atoms at a given temperature. Label the curve T1 and label the axes.[2]
2. (a)(ii)On the diagram in (a)(i), draw a second curve to show the distribution of energies of the krypton atoms at a higher temperature. Label the second curve T2.[1]
3. (b)(i)State two assumptions of the kinetic theory as applied to an ideal gas.[2]
4. (b)(ii)2.00 g of krypton gas, Kr(g), is placed in a sealed 5.00 dm³ container at 120°C. Calculate the pressure, in Pa, of Kr(g) in the container. Assume Kr(g) behaves as an ideal gas. Show your working. pressure = Pa[3]
5. (b)(iii)State and explain the conditions at which krypton behaves most like an ideal gas.[2]
6. (c)(i)Use this information to complete the reaction profile diagram for the formation of KrF₂. Label Eₐ and ∆H on the diagram. Assume the reaction proceeds in one step. [Figure 1.c.i][2]
7. (c)(ii)Explain, in terms of activation energy, Eₐ, and the collision of particles, how an increase in temperature affects the rate of a chemical reaction.[2]

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