OCR 2023 GCE Physics B H557/02: Scientific literacy in physics A Level Question Paper & Mark Scheme (Merged)

2 © OCR 2023 SECTION A 1 Digestion is an example of an activation process. The energy required for a particular molecule to break apart is 1.2 × 10–19 J. (a) (i) Calculate the Boltzmann factor for this process. Human body temperature = 310K Boltzmann factor = ..........................................................[1] (ii) Explain how an individual particle can gain sufficient energy to complete a reaction when the energy required is far greater than the average energy of the particles in the reaction. ........................................................................................................................................... ........................................................................................................................................... ...................................................................................................................................... [2] 3 © OCR 2023 Turn over The presence of an enzyme increases the Boltzmann factor of the process by a large amount. (b) (i) Explain why this change to the Boltzmann factor affects the rate at which the digestion reaction takes place. Include a description of the information the Boltzmann factor gives about the individual particles involved in an activation process. ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ........................................................................................................................................... ...................................................................................................................................... [3] (ii) The enzyme increases the Boltzmann factor at 310K to a value of 6.7 × 10–7 by reducing the activation energy required for the reaction. Calculate the activation energy of the reaction in the