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Kw Question A Level Chem

https://www.quora.com/profile/Bravewarrior/p-148537057
Here is the question and its answer. I am stuck on 6d. Can someone please explain the answer for it? Thank you so much!
Reply 1
Kw is endothermic, thus positive, as it increases with temperature
Original post by Sakai04
Kw is endothermic, thus positive, as it increases with temperature

Kw is an equilibrium constant - it can't be negative!
Original post by pigeonwarrior
https://www.quora.com/profile/Bravewarrior/p-148537057
Here is the question and its answer. I am stuck on 6d. Can someone please explain the answer for it? Thank you so much!

Kw increases with temperature.

Kw = [products]coeff/[reactants]coeff

This means at higher temperatures there are more products i.e. the equilibrium lies more to the RHS.

Hence the forward reaction is endothermic, ΔH is positive.
(edited 5 months ago)
Original post by Sakai04
Kw is endothermic, thus positive, as it increases with temperature

Ohhh ok yes this makes sense now, thank you!
Original post by charco
Kw increases with temperature.

Kw = [products]coeff/[reactants]coeff

This means at higher temperatures there are more products i.e. the equilibrium lies more to the RHS.

Hence the forward reaction is endothermic, ΔH is positive.

Thank you so much for this! It makes much more sense now 🙂
Also have they just included 25 degrees to illustrate their point about Kw increasing with temperature? As 25 degrees is not mentioned int he question anywhere
They give you two kw values at two different temperatures so that you can see the effect of increasing temperature on the equilibrium.
Original post by charco
They give you two kw values at two different temperatures so that you can see the effect of increasing temperature on the equilibrium.

Ok thanks! 🙂

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