Question

Calculate the change pf pH of an aqueous solution of 0.01 CH3 COONa If it is Diluted to10 times​

Answer 1

Answer:

The pH change when 0.01 moles of CH3COONa is added in 1 litre 0.02 M CH3COOH solution is equal to 1.25.

pKa of acetic acid is equal to 4.8 .

pH of a weak acid is equal to (pKa-logC)/2

So, pH of 0.02 M acetic acid comes out to be 3.25.

When we add sodium acetate to acetic acid the resulting solution is an acidic buffer solution.

pH of an acidic buffer solution is equal to pKa + log([salt]/[acid]).

[salt] =[sodium acetate]=0.01 M and [acid] = 0.02 M.

So, the pH = 4.5.

Therefore, change in pH=1.25.