Test 1 Pressure

[Adam Kramer 1A]

Can someone explain the question on the test asking which direction the reaction will favor if there was an increase of pressure? How does the pressure change the equilibrium of the reaction?

[J Medina 2I]

If more pressure is exerted, then the reaction will shift to the side with less moles. I like to think of the reaction as being squeezed and to adapt, the reaction overflows onto the side that is less cramped up because there is more space there.

[Elizabeth Bowen 1J]

I was confused by this one too on the test, because I thought that the reaction should favor the side with the least moles if pressure was increased, which is what I answered, but it wasn't correct so I was wondering if someone could explain that problem as well.

[nicolely2F]

If pressure is increased by compression (as opposed to other methods like increasing temperature), the reaction will shift to whichever side has fewer moles of gas in total. This means that substances in solid / liquid state should not be accounted for.

[Jasmine Kim 1L]

An increase in pressure will cause the reaction to shift towards the side with less moles.
A decrease in pressure will cause the reaction to shift towards the side with more moles.
This is because, in equilibrium, the reaction is trying to stay balanced. If the pressure changes, the system is trying to reverse this change by changing the number of moles. The amount of collisions between molecules and atoms determines pressure. The more moles there are, the more collisions there are and pressure is higher, and vice versa. Therefore, when a reaction is trying to stay in equilibrium, it will shift the number of moles so that the change in pressure is countered by the change in moles.

[005162902]

If you increase the pressure of a system, the reaction will shift to the side with less moles of gas. For example if you have 2 moles of reactant on the left and 3 moles of product on the right, the reaction will shift to the left under increased pressure because it has less moles.