Zinc reacts with hydrochloric acid according to the reaction equation
Zn(s)+2HCl(aq)⟶ZnCl2(aq)+H2(g)
How many milliliters of 4.00 M HCl(aq) are required to react with 8.25 g Zn(s)?
Zn + 2HCl ==> H2 + ZnCl2
moles Zn = grams/atomic mass = 8.25/65.4 = 0.126
mols HCl needed to react with 0.125 mols Zn = 2*0.126 = 0.252
Then M = moles/L or L = moles/M = 0.252/4.00 = 0.063
That's 63 mL