Berapa ph campuran yg terjadi bila 200 ml larutan HCOOH 0,1 mol ka10-5 dicampur Dengan 20 ml larutan HCOONa 1 mol

dik : 200ml HCOOH 0,1 mol
ka = 10^-5
20 ml HCOONa 1 mol
dit : pH campuran
jawab :
HCOOH = 200×0,1 = 20mmol
HCOONa = 20×1 = 20 mmol
[H+] = Ka×Al/garam
[H+] = 10^-5×20/20
[H+] = 10^-5
pH = 5