Changes in volume
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Changes in volume
Could someone explain how changing the volume and the moles of gas on either side of the reaction are related?
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Re: Changes in volume
Because of PV=nRT, increasing mols increases volume and decreasing mols decreases volume. They are on opposite sides of the equals sign, so they are directly proportional. In the case of K and Q, whichever side of the reaction you increase one, then the reaction will shift away from that side, but whichever side of the reaction you decrease one, then the reaction will shift towards from that side.
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Re: Changes in volume
Hi! When the volume of a system is reduced, the direction of the system will tend towards the side of the reaction that has fewer moles of gas, thus the side that will relieve the pressure within the system. And vice versa, if the volume of the system is increased, the system will tend in the direction of the side with more moles of gas, following Le Chatelier's Principle. I hope this was helpful!
Re: Changes in volume
What if we ask in terms of pressure? What happens to the reaction when pressure is increased.
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Re: Changes in volume
As volume decreases, the reaction will favor the side with less moles due to pressure differences. The opposite can be said regarding the increase of volume
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Re: Changes in volume
DArcy Perlman 1C wrote:Could someone explain how changing the volume and the moles of gas on either side of the reaction are related?
This is dependent of PV=nRT. Since moles and volume are on opposite sides of the PV=nRT equation, if one goes up so does the other. If volume increases, moles increases. If volume decreases, moles decreases.
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Re: Changes in volume
As volume decreases, system favors the direction of the reaction that has fewer moles of gas and vice versa.
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Re: Changes in volume
Katie 3H wrote:What if we ask in terms of pressure? What happens to the reaction when pressure is increased.
Pressure and volume are inversely related, and typically when a problem asks about increasing/decreasing pressure, the assumption is that volume is being increased/decreased.
When pressure is increased, volume is being decreased --> shift towards side of reaction with less gaseous moles.
When pressure is decreased, volume is being increased --> shift towards side of reaction with more gaseous moles.
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Re: Changes in volume
Volume and moles of gas are related by pressure. As we know from Le Chatelier's principle, a reaction's equilibrium will shift depending on a change provided. As such, if moles of a reactant increase, the moles of product will increase. Like wise, if moles of product increases, moles of reactants increases. If the volume increases, the side of the reaction with more moles will be favored. If the volume decreases, the side of the reaction with less moles will be favored.
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Re: Changes in volume
decreasing volume or increasing moles of gas will favor the side of the reaction with net fewer moles of gas
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Re: Changes in volume
a decrease in volume means an increase in pressure, thus the side of the reaction with fewer moles would be favored. Think about it as when there is less space available, the side of the reaction where less of the limited space is taken up is favored.
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Re: Changes in volume
Decrease in volume means that the reaction will be pushed to the side of the reaction with less moles of gas.
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Re: Changes in volume
When you decrease the volume, the reaction will favor the side with less moles of gas.
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Re: Changes in volume
Note that changing the volume does not affect the equilibrium constant because it is not in the PV=nRT equation.
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