Chemistry pH Calculation Help?

I've worked on this, and the answer I reached was:



';change in pH = 5';



Calculate the pH change when 1.0 mL of 1.0 M NaOH is added to 0.100 L of a solution of

a) 0.10 M acetic acid and 0.10 M sodium acetate.



There are others asked, but I was hoping to understand based on seeing how to do this problem, especially since I am way off!

(The real answer: ';change in pH = 0.1';) Chemistry pH Calculation Help?
pKa of acetic acid = 4.7

pH = pKa + log [CH3COO-] / [CH3COOH]

initial pH = 4.7 + log 0.10 / 0.10 = 4.7



Moles acetic acid = moles acetate = 0.10 M x 0.100 L = 0.010

Moles NaOH = 0.0010 L x 1.0 M = 0.0010



CH3COOH + OH- %26gt;%26gt; CH3COO- + H2O



moles acetic acid = 0.010 - 0.0010 =0.0090

moles acetate = 0.010 + 0.0010 =0.011



total volume = 0.101 L

concentration acetic acid = 0.0090 / 0.101 =0.089 M

concentration acetate = 0.011 / 0.101 =0.11 M



pH = 4.74 + log 0.11 / 0.089 = 4.8



dekta pH = 4.8 - 4.7 = 0.1