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Changes in Pressure, Volume, and Concentration

Posted: Tue Jan 22, 2019 10:05 pm
by juleschang16
What are the rules for Le Chatelier's Principle in response to changes in pressure, volume, and concentration?

Re: Changes in Pressure, Volume, and Concentration

Posted: Tue Jan 22, 2019 10:13 pm
by Samantha Kwock 1D
The general principle of Le Chatelier is to minimize the effects of the changes done to the system. For increases in pressure, the equilibrium can be thought of as shifting towards the side of the reaction with less moles of gas. An increase in volume would mean a decrease in pressure and concentration, and so the equilibrium would shift to the side with more moles of gas. Increasing the concentration of a particular species would shift the equilibrium away from the side that contains this species.

Re: Changes in Pressure, Volume, and Concentration

Posted: Tue Jan 22, 2019 11:10 pm
by Maayan Epstein 14B
Also something to be aware of is that if there is an increase in pressure but the same number of moles of gas on each side of the equation, then nothing happens to the system. If the question states that the PARTIAL pressure of one of the chemicals in the reaction increases, and not the total pressure of the system, then this means that you increased the amount of this chemical, and so the system will accommodate. For example, if Cl2 is a reactant and the partial pressure of this gas increases, this means that the reaction will shift toward the products, even if the products have more moles of gas.