Answer:
20 mL
Explanation:
We can determine the required volume of the concentrated (17.5 M) H₂SO₄ solution by using the C₁V₁=C₂V₂ formula:
As out of the 100 mL of the final solution, 80 mL are from the concentrated H₂SO₄ solution, the remaining 20 mL are of water (H₂O).