Hello!
The chemical neutralization reaction between NaOH and H₂SO₄ is the following:
2NaOH(aq) + H₂SO₄(aq) → Na₂SO₄(aq) + 2H₂O(l)
So, we can apply the molar equivalence at the endpoint in the following way:
[tex]moles NaOH=moles H_2SO_4*2 \\ \\ C NaOH* V NaOH=C H_2SO_4*V H_2SO_4*2 \\ \\ V NaOH= \frac{C H_2SO_4*V H_2SO_4*2}{C NaOH}= \frac{0,30 M * 20 mL * 2}{0,40 M NaOH}= 30 mLNaOH[/tex]
So, 30 mL of NaOH are required to reach an endpoint
Have a nice day!