Question

Zn (s) + 2 HCl(aq) →  ZnCl₂(aq) + H₂(g)

A student needs to react 0.175 mol Zn with hydrochloric acid. Calculate the minimum number of moles of HCl required, assuming all the zinc reacts?

Answer 1

$Zn (s) + 2 HCl(aq) → ZnCl_2(aq) + H_2(g)$

In the given reaction,

1 mole of $Zn$ requires 2 moles of $HCl$

Hence, 0.175 moles of Zn requires $0.175(2)$ = $0.35$ $moles$ of $HCl$