Increasing pressure affects the rate of reaction between hydrogen gas H and iodine gas I to form hydrogen iodide gas 2HI by increasing the frequency of collisions between the reactant molecules. This, in turn, increases the probability of successful collisions, leading to an increased rate of reaction.The balanced equation for the reaction is:H g + I g 2HI g The rate law expression for this reaction is given by:Rate = k[H]^m[I]^nwhere Rate is the reaction rate, k is the rate constant, [H] and [I] are the concentrations of hydrogen and iodine gas, respectively, and m and n are the reaction orders with respect to hydrogen and iodine.Under high-pressure conditions, the reaction is likely to be more complex, and the rate law expression may not follow a simple power-law relationship. However, for the sake of simplicity, we can assume that the reaction is elementary and follows the rate law expression mentioned above.To determine the reaction orders m and n , you would need to perform experiments under controlled conditions and analyze the data. Typically, this involves varying the concentrations of the reactants and measuring the initial rates of reaction. By comparing the changes in concentration to the changes in reaction rate, you can deduce the reaction orders.For example, if doubling the concentration of H while keeping the concentration of I constant leads to a doubling of the reaction rate, then the reaction is first-order with respect to H m = 1 . Similarly, if doubling the concentration of I while keeping the concentration of H constant leads to a quadrupling of the reaction rate, then the reaction is second-order with respect to I n = 2 .Once you have determined the reaction orders, you can write the rate law expression for the reaction under high-pressure conditions.