A gas mixture contains 4.5 mol Br2 and 33.1 mol F2. (a) Compute the mole fraction of Br2 in the mixture. (b) The mixture is heated above 150°C and starts to react to give BrF5: Br2(g) 1 5 F2(g) 8n 2 BrF5(g) At a certain point in the reaction, 2.2 mol BrF5 is present. Determine the mole fraction of Br2 in the mixture at that point.