Le Chatelier's Principle

[Clara Cho 2K]

Does change in pressure affect the concentration of the reactants and products?

[KeyaV1C]

Yes it does. Increasing the pressure of a reaction by decreasing volume favors the side of the reaction with less mols of gas. If you increase pressure by adding an inert gas, it doesn’t change the concentration of reactants or products.

[aishwarya_atmakuri]

If the change in pressure changed the volume, it affects the concentration. If the change in pressure was caused by the addition of an intert gas, the volume hasn't changed so the concentrations have not changed.

[Keya Jonnalagadda 1A]

As an addition to the earlier replies: Although changing the pressure changes the concentration of the products and reactants, their ratio will return to the equilibrium constant, Kp. Only a change in temperature changes Kp, not the pressure or concentration of products and reactants.

[rohun2H]

Yes, but K remains constant.

[Miriam Villarreal 1J]

When there is an increase in pressure, the equilibrium will shift towards the side of the reaction with fewer moles of gas. When there is a decrease in pressure, the equilibrium will shift towards the side of the reaction with more moles of gas.

[Bilal Pandit 1J]

When the pressure changes, then the Q will be different than the Kp, so you can figure out which way the experiment will shift according to that.