Find the pH of 1.0M Na2SO3(aq) solution at 25 degrees Celsius.

Question

I am not sure how to start this problem.

I started off by doing 1.0M = x/1000 to get x=0.001 but I do not know if this is how to start.

Answer 1

This is done exactly like a similar problem with acetic acid. The only difference is that acetic acid is a monoprotic acid and H2SO3 is a diprotic but we get around that by noting that k2 for H2SO3 is so much smaller than k1 so we just ignore the k2 and act as though H2SO3 were a monoprotic acid with kl as Ka.

Answer 2

SO I have to figure out what k1 is?

Answer 3

Look it up in your text. Mine shows it as 1.72E-2 but your text may have a slightly different value.

Answer 4

Hannah, I have led you astray. I misread the question and answered as if it were an acid; it isn't an acid, it's a salt. So it is worked as the hydrolysis of a salt instead of the directions I gave. I caught my error when I answered the same question for Mohammad. Here is the link to that response. Sorry about that.
http://www.jiskha.com/display.cgi?id=1333483122