In: Chemistry
Determine the [H3O+] and [OH-] for the following:
A 100 mL solution of .400 M Sodium Acetate (NaOAc) mixed with 100 ml of .400 M HCl.
When we add HCl to the Sodium Acetate (NaOAc) solution,it forms a buffer solution.
pH for the buffer solution can be calculated by using Handerson's equation.
pH = pKa + log [salt]/[acid]
for acetic acid buffer , pKa = 4.74
we need to calculate [salt] and [acid]
NaOAc + HCl ------------------> AcOH + NaCl
100ml x 0.4M 100ml x 0.4M 0 0
at t=0 = 0.1L x 0.4M 0.1L x 0.4M 0 0
= 0.04moles 0.04moles 0 0
after the reaction
(0.04-0.04) moles (0.04-0.04) moles 0.04moles
Hence salt NaOAc reacts completely after the reaction.
We cannot calculate the pH and then [H3o+] and [OH-]