How much hcl can be produced by reacting 0.8g of hydrogen with excess of chlorine

The balanced chemical reaction will be:

H2 + Cl2 = 2HCl

We are given the amount of reactants and since chlorine is in excess we can say that all of the hydrogen supplied will be in complete reaction. This will be our starting point.

0.8 g H2 (1 mol H2 / 2.02 gH2) (2 mol HCl/1mol H2) ( 36.46 g HCl/1mol HCl) = 28.88 g HCl

Thus, the answer is 28.88g H2O.