00:01
The first part of the question is we need to find the kb for the conjugate base of an unknown acid having a ka value that is 7 .6 into 10 rise to minus 3 which is reduced to the highest power possible.
00:26
Here it is given that ka which is the acid dissociation constant.
00:39
Kb is the base dissociation constant.
00:45
And for conjugate acid base pair, here we know that for this, ka into kb is equal to kw, where kw is the ionic product of water at 25 degrees celsius.
01:14
And the value of kw is, 1 into 10 rise to minus 40.
01:21
Now putting the given value k, we get kb is equal to ka by kw.
01:30
That is ka is 7 .6 into 10 rise to minus 3 by kw is 1 into 10 rise to minus 40.
01:40
Thus kb is obtained as 7 .6 into 10 rise to 12.
01:52
Now, the second part of the question is that we need to find the ph of a solution with the hydroxide concentration of 6 .7 into 10 rise to minus 5 molar...