It is a simple stoichiometry problem. We have been given with balanced equation and 5.00 moles of HCl and have to calculate the moles of H2.
<span>From the balanced equation it is being clear that 2 moles of HCl are produced by 1 mole of H2. so, 1 mole of HCl will be produced by 1/2 moles of H2. So, the mole ratio of H2 and HCl is 1:2 </span> <span>to calculate the moles of H2 for the given moles of HCl, multiply the moles of HCl by the mole ratio of H2 and HCl. </span>
<span>5.00 mole HCl x (1 mole H2/ 2 mole HCl) </span> <span>= 2.50 mole H2 </span> <span>so, to produce 5.00 moles of HCl, 2.50 moles of H2 are required.</span>
