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So in one of the TBR passages, the following reaction is given.
A(g)+B(g)<->C(g)
Since the passage talks about equilibrium, I'm assuming that the reaction takes place in a closed system.
Once the reaction reaches equilibrium, stress is applied to the system, that is external pressure is doubled.
Before this change, partial pressure of each gas was 1 atm, after the stress is applied, it doubled to 2 atm each. But by La Chatelier's principle, the reaction shifts to right (because it's the side with less number of gas molecules) to reduce the pressure of the system.
My questions are
1) What is external pressure? Say if the reaction takes place in a closed jar, can external pressure be the atmostpheric pressure surrounding the jar?
2) Why does increasing the external pressure also increase the system partial pressures by exactly same degree (x2) at least for initially?
3) Shouldn't (External pressure) = (Total system pressure: sum of all partial pressures)? Initially total system pressure is 3 atm, so external pressure must be 3 atm. Later, the external pressure is jumped to 6 atm, but the system pressure would be less than 6 (due to shifted equilibrium, the particular example in the book shows 5.56 atm as the last total pressure). How is this discrepancy accounted for?
I'd apprecaite for any comments.
A(g)+B(g)<->C(g)
Since the passage talks about equilibrium, I'm assuming that the reaction takes place in a closed system.
Once the reaction reaches equilibrium, stress is applied to the system, that is external pressure is doubled.
Before this change, partial pressure of each gas was 1 atm, after the stress is applied, it doubled to 2 atm each. But by La Chatelier's principle, the reaction shifts to right (because it's the side with less number of gas molecules) to reduce the pressure of the system.
My questions are
1) What is external pressure? Say if the reaction takes place in a closed jar, can external pressure be the atmostpheric pressure surrounding the jar?
2) Why does increasing the external pressure also increase the system partial pressures by exactly same degree (x2) at least for initially?
3) Shouldn't (External pressure) = (Total system pressure: sum of all partial pressures)? Initially total system pressure is 3 atm, so external pressure must be 3 atm. Later, the external pressure is jumped to 6 atm, but the system pressure would be less than 6 (due to shifted equilibrium, the particular example in the book shows 5.56 atm as the last total pressure). How is this discrepancy accounted for?
I'd apprecaite for any comments.