What is the pH of .1M of CH3COONa??

Question

I got 8.9, is that right?

Answer 1

Yes it is. Since you have found the correct value I'll only mention briefly the solution
CH3COOH has pKa=4.76, thus CH3COO- has pKb=14-4.76=9.24

Kb= x^2/(0.1-x)
We assume 0.1>>x => x= squareroot(0.1*Kb) = 7.59*10^-6 which means that the assumption is valid and then
pH=14-pOH= 14-(-log(7.59*10^-6)) =8.88 =8.9