Concentration and le chateliers principle

When looking at concentration and le chateliers principle should I look t the number of moles r is that only for pressure

Reply 1

Ekt_0678

Original post by Animal lover :))

When looking at concentration and le chateliers principle should I look t the number of moles r is that only for pressure

Concentration does not affect the position of equilibrium in Le Chatelier's principle. Only temperature and pressure.

Reply 2

Pigster

Original post by Animal lover :))

When looking at concentration and le chateliers principle should I look t the number of moles r is that only for pressure

I am answering this assuming you're an A level student. If you're only GCSE, let me know and I'll translate into simpler language.

Pressure and concentration affect equilibrium positions in the same way as they are just two different ways of measuring the same thing - how many particles there are in a given volume. One directly counts the particles, the other indirectly by seeing the effect they have on the walls of the container.

If you have the same number of particles on both sides, and you change the volume (which will affect all concs OR will change the P), then the equilibrium position doesn't change. Kc and Kp don't change.

If you have more particles on one side, changing the volume or P will shift the equilibrium position BECAUSE Kc and Kp are constant.

Changing T always shifts the equilibrium position. i.e. Kc and Kp does change.