[student8607]

GIVEN: 0.1M H₂SO₃ with a Ka₁ = 1.5x10^-2 & a Ka₂ = 6.3x10^-8

I made my ice chart and solved for..
[H₂SO₃] = 0.07
[H₃O⁺] = 0.03
[OH^-] = 3.1x10^-13
[HSO₃^-] = 0.03
pH = 1.49
....all of that verified with the book answers

So I'm doing the second reaction and I have it set up

6.3 x 10^-8 = x² / 0.07

I get that [SO₃^2-] is 3.64x10^-5, but the book has 3.64x10^-8. How?

[Borek]

6.3 x 10^-8 = x² / 0.07

Why do you ignore H⁺ from the first dissociation step?

http://www.chembuddy.com/?left=pH-calculation&right=pH-polyprotic-simplified

[student8607]

6.3 x 10^-8 = x² / 0.07

Why do you ignore H⁺ from the first dissociation step?

http://www.chembuddy.com/?left=pH-calculation&right=pH-polyprotic-simplified

Whoops.
Got it now.

Thanks.