If you have CL2 + H2o ---> H+ + Cl- + HOCl
and you are given [HOCl] = 0.06 M
and you have to find pH....
can you assume that [HOCl] =[H+] = 0.06 M
since H+ and HOCl both have a coefficient of 1?
Thank you
3 answers
Answered elsewhere.
So if I can't assume that, then how can I calclate pH? I don't know K value, so I can't use Henderson Hasselbalc...
Kiki--It's the next day and I have a clearer head than when I read your problem the first time last night. I just did not read your question properly (and the small o in H2o threw me off, too). Of course, if HOCl is 0.06 M, then H^+ is 0.06 M and Cl^- is 0.06 M. You may want to recognize that HOCl is a weak acid; therefore, it will provide some hydrogen ions additional to the H^+ and Cl^- from the reaction but the amount will be decreased, due to Le Chatelier's principle. That is
HOCl ==> H^+ + OCl^-
Ka = (H^+)(OCl^-)/(HOCl)
If (H^+) = 0.06 = (HOCl), then (OCl^-) = Ka
Total H^+ then is 0.06 from HCl part and Ka (whatever that value is) from the HOCl part. I suspect the H^+ from HOCl will be so small that it is negligible.
HOCl ==> H^+ + OCl^-
Ka = (H^+)(OCl^-)/(HOCl)
If (H^+) = 0.06 = (HOCl), then (OCl^-) = Ka
Total H^+ then is 0.06 from HCl part and Ka (whatever that value is) from the HOCl part. I suspect the H^+ from HOCl will be so small that it is negligible.