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le chapeliers principle, exo and endo?????

I keep getting the equilibrium shift questions wrong so im checking im correct in thinking exothermic will increase the temp and endothermic reaction will decrease the temperate. If that is correct does anyone have a way of remembering which is increase and which is decrease
Original post by sg.0
I keep getting the equilibrium shift questions wrong so im checking im correct in thinking exothermic will increase the temp and endothermic reaction will decrease the temperate. If that is correct does anyone have a way of remembering which is increase and which is decrease
Remember system always opposes the change you make at equilibrium so:
Increase temperature (in the surroundings containing the system), system wants to decrease temperature, remember endothermic reactions decrease temperature (energy from the surrounding to the system), so equilibrium shift to the endothermic direction.

Decrease temperature (of surrounding), system wants to increase temperature, exothermic reactions increase temperature (energy from system to surroundings, equilibrium position to exothermic direction.

You were right about exothermic (increase temperature) and endothermic (decrease temperature), but it seems you were getting confused about which direction equilibrium shifts to when you change temperature.
(edited 2 months ago)
Reply 2
Original post by sg.0
I keep getting the equilibrium shift questions wrong so im checking im correct in thinking exothermic will increase the temp and endothermic reaction will decrease the temperate. If that is correct does anyone have a way of remembering which is increase and which is decrease

See above answer for explanation. If you need help remembering which is which, consider the prefixes exo- and endo- which mean "out of" and "into" respectively.

So exothermic reaction releases energy from the system out to the surroundings (raises temperature), and endothermic takes energy into the system from the surroundings (lowers temperature).
Reply 3
Original post by BankaiGintoki
Remember system always opposes the change you make at equilibrium so:
Increase temperature (in the surroundings containing the system), system wants to decrease temperature, remember endothermic reactions decrease temperature (energy from the surrounding to the system), so equilibrium shift to the endothermic direction.
Decrease temperature (of surrounding), system wants to increase temperature, exothermic reactions increase temperature (energy from system to surroundings, equilibrium position to exothermic direction.
You were right about exothermic (increase temperature) and endothermic (decrease temperature), but it seems you were getting confused about which direction equilibrium shifts to when you change temperature.
thank you im always getting confused as to which way it shifts due to confusing endo and exo but that's helped a lot thank you
Reply 4
Original post by Methene
See above answer for explanation. If you need help remembering which is which, consider the prefixes exo- and endo- which mean "out of" and "into" respectively.
So exothermic reaction releases energy from the system out to the surroundings (raises temperature), and endothermic takes energy into the system from the surroundings (lowers temperature).
thank you that really helps

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