Question

What is the minimum amount of 6.7M H2SO4 necessary to produce 27.9g of H2 (g) according to the following reaction? 2Al(s)+3H2SO4(aq)→Al2(SO4)3(aq)+3H2(g)

I don't know how to solve it, and I don't understand the explanation
given online.

Answer 1

You worked all of those stoichiometry problems (even the limiting reagent problem) beautifully that I checked last night. This is the same thing with just a slight twist at the end.
2Al(s)+3H2SO4(aq)→Al2(SO4)3(aq)+3H2(g)

mols H2 = grams/molar mass = ?
Using the coefficients in the balanced equation, convert mols H2 to mols H2SO4.
Then M H2SO4 = mols H2SO4/L H2SO4. You know mols from above and M from the problem, solve for L H2SO4. Convert to mL if you wish.