if the pH of rain water is 5.6 on average what is the concentration of carbonic acid in rain water?

2 answers

If the pH of rain water is 5.6 on average what is the concentration of carbonic acid in rain water?
...........H2CO3 ==> H^+ + HCO3^-
initial......x.......0.......0
change..........2.51E-6..2.51E-6
equil.......x-2.51E-6
K = (H^+)(HCO3^-)/(H2CO3)
Substitute and solve for x.
Watch out. The H^+ from neutral water is 1E-7 and that's very close to this value. You may not be able to neglect that.