What is the pH of the solution created by ?

Question

combining 12.60 mL of the 0.10 M NaOH(aq) with 8.00 mL of the 0.10 M HCl(aq)?

with 8.00 mL of the 0.10 M HC2H3O2(aq)?

What are the pH values if you take into account that the 8.00 mL of 0.10 M Acid was first diluted with 100 mL of water?

Answer 1

Moles NaOH = 0.01260 L x 0.10 = 0.001260

Moles HCl = 0.0080 L x 0.10 = 0.00080

Moles OH- in excess = 0.00046

total volume = 0.0206 L

[OH-] = 0.00046/ 0.0206 =0.0223 M

pOH =1.65

pH = 14 - 1.65 = 12.35

If the acid is a weak acid this does not affect the pH because the concentation of H+ is in excess