Question

if 0.30 mol of zinc are added to 0.52 mol of hcl ,the moles of h2 formed are

Answer 1

since 1 mole of Zinc requires 2 Moles of HCl. i.e zn + 2 HCl --- > ZNCl2 + H2
 
Given, 0.52 of HCl i.e 0.52/2 = 0.26moles

Answer 2

Answer: The moles of $H_2$ formed are 0.26 moles.

Explanation:

The chemical equation for the reaction of zinc and hydrochloric acid follows:

$Zn+2HCl\rightarrow ZnCl_2+H_2$

By Stoichiometry of the reaction:

2 moles of hydrochloric acid reacts with 1 mole of zinc metal.

So, 0.52 moles of hydrochloric acid will react with = $\frac{1}{2}\times 0.52=0.26mol$ of zinc metal.

As, the given amount of zinc is more than the required amount. Thus, it is considered as an excess reagent.

Hydrochloric acid is a limiting reagent because it limits the formation of products.

By Stoichiometry of the reaction:

2 moles of hydrochloric acid produces 1 mole of hydrogen gas.

So, 0.52 moles of hydrochloric acid will produce = $\frac{1}{2}\times 0.52=0.26mol$ of hydrogen gas.

Hence, the moles of $H_2$ formed are 0.26 moles.