Destroyer general chem q 87

[SING]

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Consider the following:
H2O (l) + H2O(l) ==> OH(aq) + H3O(aq)
When the temperature is decreased from 25 degree Celsius, it is found that the kw has increased. which of the following is true?

A. The reaction must be exothermic

B. The reaction must be endothermic

C. The reaction is thermo neutral

D. Not possible, Kw = 1*10^-14 at all the temperatures

E. None of these.
Increasing the T will favor the endothermic and decreasing T will favor the exothermic. This explanation doesn't make sense. can somebody please help? Thanks

 

[hockey553]

So it is saying when temperature is decreased then the kw has increased (reaction shifts right). Which side must the heat be on?

heat + H2O (l) + H2O(l) ==> OH(aq) + H3O(aq)

H2O (l) + H2O(l) ==> OH(aq) + H3O(aq) + heat

Reaction must be exothermic because decreasing heat shifts reaction towards the products which increases kw

 

[SING]

I am sorry. I should have posted the whole answer.
The answer is endothermic since the rxn T is decreasing , but the Kw has gotten smaller means that reaction does not favor the exothermic reaction, thus must be endothermic.