N2 (g) + H2 (g) <--> NH3 (g) + energy

Name the direction of equilibrium shift

- The pressure of the system is increased.

- H2 is added to the system.

- The temperature of the system is decreased.

N2 (g) + 3H2 (g) <--> 2NH3 (g) + energy

The reaction will shift (forward direction or reverse direction) in order to undo what we've done to it.
Pressure is increased. The system will shift to decrease the pressure. How can it do that? By moving to the side with the fewer mols. There are 4 mols on the left and 2 on the right; therefore, it will shift to the right.

So for temperature, would it shift to the left?

If T is increased it will go to the left in order to use up the heat (energy) that has been added. Decreasing T will make it try to heat up so will go to the right.

23-12=01

In order to determine the direction of equilibrium shift for each scenario, we need to consider Le Chatelier's principle. According to this principle, when a chemical system at equilibrium is subjected to a change in conditions, the system will respond in a way that counteracts the change. By understanding the effect of each change on the equilibrium, we can predict the direction of the shift.

1. The pressure of the system is increased:
When the pressure of a gas-phase equilibrium is increased, the system shifts in the direction that decreases the total number of gas molecules (or moles of gas). In this reaction, there are a total of 3 moles of gas on the left side (N2 + H2) and 2 moles of gas on the right side (NH3). Increasing the pressure would cause the system to shift in the direction that decreases the total number of moles of gas, which is towards the right (towards NH3). Therefore, the equilibrium will shift to the right.

2. H2 is added to the system:
Adding a reactant to an equilibrium system shifts the equilibrium in the direction of the products in order to consume the excess reactant. In this case, adding H2 gas will increase the concentration of H2. To reduce this excess concentration, the equilibrium will shift towards the products (NH3). Therefore, the equilibrium will shift to the right.

3. The temperature of the system is decreased:
A decrease in temperature favors the exothermic direction of a reaction (the direction that releases heat). In this reaction, NH3 is formed with the release of energy. Therefore, decreasing the temperature will favor the formation of NH3, and the equilibrium will shift towards the right.

In summary,
- When the pressure is increased, the equilibrium shifts to the right (towards NH3).
- When H2 is added, the equilibrium also shifts to the right (towards NH3).
- When the temperature is decreased, the equilibrium shifts to the right (towards NH3).