Can anyone answer this question please.

Question

(Determine the concentration of an aqueous NaCl solution if 31.5 mL are required to reach
the equivalence point when titrated with 25.0 mL of 0.20 M AgNO3.)

Answer 1

Since the reaction is 1:1
AgNO3 + NaCl ==> AgCl + NaNO3

You can use the simple fomula of
mL x M = mL x M. This can not be used with the ratio is other than 1:1.

Answer 2

61.0 mL of a 1.50 M solution is diluted to a volume of 258 mL. A 129-mL portion of that solution is diluted using 167 mL of water. What is the final concentration?

Answer 3

Calcuted mole fraction of HCl in a solution containing 24.8%HCl by mass