# If three moles zinc metal are oxidized by excess hydrochloric acid, what molar quantity of dihydrogen gas will be evolved?

Feb 22, 2017

$\text{Three moles of dihydrogen gas will be evolved. }$

#### Explanation:

We need a stoichiometric equation that represents the oxidation of zinc metal by an acid:

$Z n \left(s\right) + 2 H C l \left(a q\right) \rightarrow Z n C {l}_{2} \left(a q\right) + {H}_{2} \left(g\right) \uparrow$

Given the stoichiometry, if $3.0 \cdot m o l$ zinc metal react, then, given the stoichiometry of the reaction, $\text{3 mol dihydrogen gas}$ will be evolved. All I am doing is following the stoichiometry of the balanced equation. Do you agree?

What does $\text{stoichiometric}$ mean?