[Phoebe]

 Ok - I've another question I'm uncertain about.
 
This time I'm asked: If a highly concentrated ammonia solution is found to have a pH of 12.08. What is the hydroxide concentration [OH^-(aq)] in mol L^-1
(give answer to at least 3 sig figs)

So pH = 12.08, pOH is 14 - 12.08 pOH = 1.92,

Here's where I get confused:

I think to calculate the OH^- I do [OH^-] = 10^-1.92

and get an answer of = 0.0120 mol L^-1

But I'm not sure that's right, can anyone tell me if I've gone off track?

[AWK]

OK

[Vidya]

Ok - I've another question I'm uncertain about.
 
This time I'm asked: If a highly concentrated ammonia solution is found to have a pH of 12.08. What is the hydroxide concentration [OH^-(aq)] in mol L^-1
(give answer to at least 3 sig figs)

So pH = 12.08, pOH is 14 - 12.08 pOH = 1.92,

Here's where I get confused:

I think to calculate the OH^- I do [OH^-] = 10^-1.92

and get an answer of = 0.0120 mol L^-1

But I'm not sure that's right, can anyone tell me if I've gone off track?

Perfect and even sig -figs are also correct.