How do I find the pH, pOH, [OH -1], and [H +1]?

Question

0.195 moles of Ba(OH)2 in 1250.0 mLs H2O

How do I find these values:

pH = ?

pOH = ?

[OH -1] = ?

[H +1] = ?

and also, is it Acidic or Basic?

Answer 1

n(Ba(OH)2)= 0,195 mol

V(H2O)= 1250,0 mL=1,250L

n=cV   c=n/V

c(Ba(OH)2)=0,195 mol/1,250L=0,156mol/L

Ba(OH)2-------> (Ba^2+) + 2OH^ -1

you see that the concentration of OH is twice bigger than that one of Ba(OH)2, so c(OH^ -1)=0,312

pOH= - logc(OH^ -1)= -log 0,312= 0,5

pKw=pH+pOH

pKw=14 because Kw= 1x10^-14

pH=pKw-pOH

pH=14-0.5

pH=13,5 it is basic

c(H^+1)= 10^-ph

c(H^+1)= 10^(-13,5)=3,6x10^-14

something like that