Question

What volume of 0.0748 M perchloric acid can be neutralized with 115 mL of 0.244 M sodium hydroxide?

Answer 1

Answer:

0.375 L

Explanation:

We know that at neutralization, the number of mol  of acid must equal the number of equivalents of base.

This is a reaction 1:1 acid to base:

HClO₄ + NaOH ⇒ NaClO₄ + H₂O

We re given the  moles  of the base indirectly since we know the volume and molarity. From there we can calculate the volume of HClO₄.

Moles NaOH = 0.115 L x 0.244 M = 0.115 L x 0.244 mol/L =0.028 mol

Thus we require 0.028 mol of HClO₄ in the pechloric acid solution:

Molarity = # moles / V ⇒ V = # moles / M

V = 0.028 mol / 0.0748 mol/L = 0.375 L

Note  that this problem can be solved in just one step since

M(HClO₄) x V(HClO₄) = M(NaOH) x V(NaOH)  ⇒

V(HClO₄) = M(NaOH) x V(NaOH) / M(HClO₄)