The titration of 24.30 mL of HCl solution of unknown concentration requires 12.84 mL of a 0.120 M NaOH solution to reach the equivalence point. What is the concentration of the unknown HCl solution in M?

0.0634 M HCl

Explanation:

Since HCl and NaOH react in a one-to-one mole ratio, we can just use M1V1 = M2V2 to solve for M1 (the concentration of HCl)

M1 = ? M HCl

V1 = 24.30 mL HCl

M2 = 0.120 M NaOH

V2 = 12.84 mL NaOH

M1(24.30 mL HCl) = (0.120 M NaOH)(12.84 mL NaOH)

M1 = 0.0634 M HCl

the answer is b & c i believe : )