How many ml of a .25M HCL would be required to neutralize completely 2.5g of NaOH

Answer 1

Write the equation and balance it.

NaOH + HCl ==> NaCl + H2O

mols NaOH = 2.5g/molar mass NaOH.
mols HCl required = mols NaOH (from the equation).
Then mol HCl = M(HCl) x L(HCl). You have the molarity of the HCl and you have the mols of HCl from your calculation, which leaves just one unknown (the L). Convert that to mL.