Le Chatelier's Principle and Partial Pressure

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005115864
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Joined: Thu Sep 27, 2018 11:15 pm

Le Chatelier's Principle and Partial Pressure

Postby 005115864 » Sat Jan 19, 2019 3:38 pm

In question 11.69b, form the 6th edition, the formula given is CO + H20 > CO2 + H2. It asks what will happen to the partial pressure of CO2 if the partial pressure of CO is reduced.

What I don't understand is why does reducing the partial pressure of CO decrease the amount of CO2. I thought using Dalton's law of partial pressures, we could assume that since the partial pressure of CO went down, then the partial pressure of H20 went up and not affect the partial pressure of CO2. Can someone clarify why pressure has an effect on other pressure?

deepto_mizan1H
Posts: 50
Joined: Thu Sep 27, 2018 11:16 pm

Re: Le Chatelier's Principle and Partial Pressure

Postby deepto_mizan1H » Sat Jan 19, 2019 4:15 pm

Le Chatelier's principle tries to explain how the system will try to reduce the stress put on it. If the system loses pressure or (loss of concentration) on one side, the system can push towards the reverse (or whichever direction) it requires in order to equalize. In this case, it'll reduce on the right side because it's pushing towards the left in order to go back to equilibrium. I may be wrong on the specifics but the general idea of balance is what we follow.

sophiebillings1E
Posts: 45
Joined: Thu Sep 27, 2018 11:27 pm

Re: Le Chatelier's Principle and Partial Pressure

Postby sophiebillings1E » Sat Jan 19, 2019 4:18 pm

Partial pressures change when product or reactant are removed or added to the system.

caseygilles 1E
Posts: 56
Joined: Thu Sep 27, 2018 11:18 pm

Re: Le Chatelier's Principle and Partial Pressure

Postby caseygilles 1E » Sun Jan 20, 2019 5:25 pm

Reducing the partial pressure of CO decreases the pressure of CO2 because the system looks to minimize the effect of changes. Therefore, if pressure of CO is decreased, the reaction will shift to increase CO back to its pressure and so the reaction shifts left, thus the products are being consumed to form more reactants, so CO2 decreases and CO increases back to the equilibrium constant ratio it had before.


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