Answer: 10 grams of Hydrogen gas will be produced theoretically.
Explanation: The equation for the reaction between zinc metal and hydrochloric acid is:
[tex]Zn(s)+2HCl(aq.)\rightarrow ZnCl_2(aq.)+H_2(g)[/tex]
As HCl is present in excess, therefore limiting reagent is Zinc metal as it limits the formation of product.
By stoichiometry,
1 mole of Zinc metal produces 1 mole of Hydrogen gas, therefore
[tex]\text{5 moles of Zinc metal will produce}=\frac{1}{1}\times 5=5\text{ moles of Hydrogen gas}[/tex]
Amount of Hydrogen gas produced can be calculated by:
[tex]\text{Mass of gas produced}=\text{Moles}\times \text{Molar mass}[/tex]
Molar mass of Hydrogen = 2 g/mol
Mass of hydrogen gas produced = (5 moles )× (2 g/mol)
Mass of hydrogen gas produced = 10 grams
