I cannot figure out the equation and answer to the following. Can someone help please.

Question

A 25.0 mL solution of HCl has been spilled. It took 21.8 mL of saturated 2.5 M NaOH to neutralise the acid. What was the molar concentration of the acid?

Answer 1

HCl + NaOH ==> NaCl + H2O

mols NaOH used = M x L = ?
mols HCl neutralized = mols NaOH
M HCl = mols HCl/L HCl

Answer 2

I think this was asked before:
w ww.jiskha.c om/display.cgi?id=1375933614

Answer 3

Is Sarah the same as Campbell?