Consider the reaction:
2Al(s) + 3 H2SO4(aq) → Al2(SO4)3(aq) + 3 H2(g)
What minimum volume of 4.0 M H2SO4 is required to produce 15.0 L of H2 at STP?
Answer :
Step 1</p>write a balanced chemical equation for this single replacement reactionuse the molar volume of a gas at STP to find the number of moles of hydrogen gas present in that volumeuse the mole ratio that exists between sulfuric acid and hydrogen gas to find the number of moles of the former needed to produce that many moles of the latteruse the sulfuric acid solution's molarity to find the volume that would contain that many moles of sulfuric acid.
Step 2</p>
So, the balanced chemical equation for this reaction looks like this
2Al(s]+3H2SO4(aq]→Al2(SO4)3(aq]+3H2(g]↑
As you know, STP conditions are characterized by a pressure of 100.0 kPa and a temperature of 0∘C. Under these conditions, one mole of any ideal gas occupies exactly 22.71 L - this is the molar volume of a gas at STP.