Question

Calculate the pH of each of the following solutions.
(a) 7.5 10-4 M Ba(OH)2



(b) 4.3 10-4 M HNO3

Answer 1

a)

Ba(OH)2 <--->Ba2+ + 2OH-

[OH-]= [Ba(OH)2]
^1/2
[OH-]=0.0274
pOH=-log[OH]=1.562
pH=14-pOH=14-1.562=12.438

b)
HNO3<--->H+
+ NO3-
[H+]=[HNO3]=4.3 10-4
pH=-log[H+]=3.366