What is the ion-product constant, #K_w#?

1 Answer
Jun 11, 2017

Answer:

For water, this is the measure of the #"autoprotolysis reaction"#....

Explanation:

#2H_2O(l) rightleftharpoonsH_3O^+ + HO^-#

And #K_w=[HO^-][H_3O^+]=10^-14# at #298*K#.

And when we take #-log_10# of both sides we get the useful expression...........

#pH+pOH=14#, where #pH=-log_10[H_3O^+]# etc.

How do you think #K_w# would develop if non-standard conditions pertained; e.g. if temperature was say #373*K#. Would #K_w# remain constant, decrease, increase? Remember that the autoprotolysis reaction as shown is a #"bond-breaking reaction"#.