How would the addition of hydrogen gas at constant temperature and volume effect rate=k[h2][I2]?

It would increase the rate of the reaction. Looking at the equation should allow you to notice this. In general there are three factors that can affect the rate of a reaction:

1.) reactant concentrations
2.) catalysts
3.) temperature

To determine how the addition of hydrogen gas at constant temperature and volume affects the rate of the reaction represented by the equation rate = k[H2][I2], we need to understand the concept of reaction rate and how it is influenced by changes in concentration.

In this equation, the rate of the reaction is directly proportional to the concentrations of hydrogen gas ([H2]) and iodine gas ([I2]), represented by the square brackets. The constant k is the rate constant, which depends on the specific reaction and temperature.

When we add more hydrogen gas to the system while keeping the temperature and volume constant, only the concentration of hydrogen gas will change. The concentration of iodine gas remains unaffected.

If we increase the concentration of hydrogen gas, it will result in an increase in the overall rate of the reaction. This is because the rate of a chemical reaction generally increases with increasing reactant concentration. According to the rate law equation rate = k[H2][I2], if we increase the concentration of hydrogen gas ([H2]), the rate of the reaction will also increase, assuming the concentration of iodine gas ([I2]) remains constant.

Conversely, if we decrease the concentration of hydrogen gas, the rate of the reaction will decrease, assuming all other factors remain constant. This is because the reaction rate is directly proportional to the concentration of hydrogen gas.

In summary, adding more hydrogen gas at constant temperature and volume will increase the rate of the reaction represented by the equation rate = k[H2][I2]. Conversely, reducing the concentration of hydrogen gas will result in a decrease in the reaction rate.