In: Chemistry
What is the pH of a 0.445 M ammonia solution? Express your answer numerically to two decimal places.
NH3(aq) + H2O(l) -------------> NH4^+ (aq) + OH^- (aq)
I 0.445 0 0
C -x +x +x
E 0.445-x +x +x
Kb = [NH4^+][OH^-]/[NH3]
1.8*10^-5 = x*x/(0.445-x)
1.8*10^-5 *(0.445-x) = x^2
x = 0.00282
[OH^-] = x = 0.00282M
POH = -log[OH^-]
= -log0.00282
= 2.5497
PH = 14-POH
= 14-2.5497
= 11.45 >>>>>answer