Question

Methane reacts with steam, and an equilibrium is reached.

CH4(g) + H2O(g) ⇌ CO(g) + 3H2(g)
The forward reaction is endothermic. Which row shows how the amount of hydrogen at equilibrium changes when the pressure or temperature is changed as indicated?
A) Change in temperature: Decrease, Change in pressure: No change, Amount of hydrogen: Increase
B) Change in temperature: Increase, Change in pressure: No change, Amount of hydrogen: Decrease
C) Change in temperature: Decrease, Change in pressure: Increase, Amount of hydrogen: No change
D) Change in temperature: Decrease, Change in pressure: Decrease, Amount of hydrogen: No change

Answer 1

The amount of hydrogen at equilibrium increases when the temperature is increased in the endothermic methane and steam equilibrium reaction, while the pressure does not have an effect on the amount of hydrogen. correct option is D) Change in temperature: Decrease, Change in pressure: Decrease, Amount of hydrogen: No change.

Step-by-step explanation:

The forward reaction of the methane and steam equilibrium is endothermic, meaning that it absorbs heat. When the temperature is increased, the equilibrium will shift in the endothermic direction to absorb more heat. As a result, the amount of hydrogen at equilibrium will increase.

On the other hand, changing the pressure does not affect the amounts of the substances involved in the equilibrium since no gases are added or removed. Therefore, the amount of hydrogen at equilibrium will remain the same when the pressure is changed. Based on these observations, the correct row showing how the amount of hydrogen at equilibrium changes is D) Change in temperature: Decrease, Change in pressure: Decrease, Amount of hydrogen: No change.