For the following exothermic reaction, the rate law at 298 K is rate = k [H₂][I₂].H₂(g) + I₂(g) $\rarr$ 2HI(g) Which of the following, if any, would cause the rate of the reaction to increase
1. Addition of hydrogen gas at constant temperature and volume
2. Increase in volume of the reaction vessel at constant temperature
3. Addition of a catalyst
4. Increase in temperature

Question

For the following exothermic reaction, the rate law at 298 K is rate = k [H₂][I₂].H₂(g) + I₂(g)

\rarr

2HI(g) Which of the following, if any, would cause the rate of the reaction to increase
1. Addition of hydrogen gas at constant temperature and volume
2. Increase in volume of the reaction vessel at constant temperature
3. Addition of a catalyst
4. Increase in temperature

Quizplus · Accepted Answer

1. Addition of hydrogen gas at constant temperature and volume: This would increase the concentration of H2 and therefore increase the rate of the reaction based on the rate law provided. 2. Increase in volume of the reaction vessel at constant temperature: This would decrease the concentration of both reactants, H₂ and I₂, resulting in a decrease in their collision frequency and, therefore, a decrease in the rate of the reaction. Thus, this would not increase the rate. 3. Addition of a catalyst: A catalyst increases the rate of the reaction by providing an alternative pathway with a lower activation energy. Therefore, the rate of the reaction would increase in the presence of a catalyst. 4. Increase in temperature: An increase in temperature will increase the kinetic energy of the molecules, causing more collisions and therefore increasing the rate of the reaction based on the rate law provided.

For the Following Exothermic Reaction, the Rate Law at 298 →\rarr→

For the Following Exothermic Reaction, the Rate Law at 298 $\rarr$