# What volume of 20%(w/w) "hydrochloric acid" are need to oxidize a mass of 130*g "zinc metal"?

Apr 15, 2017

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

#### Explanation:

Now it is a fact that 20%(w/w) $H C l$ has a molar concentration of $6.0 \cdot m o l \cdot {L}^{-} 1$. To calculate this you should have been given more details in the question.

We require a TWICE molar quantity with respect to the moles of zinc.

$\text{Moles of zinc} = \frac{130 \cdot g}{65.4 \cdot g \cdot m o {l}^{-} 1} = 2.0 \cdot m o l$

And thus we need $\frac{1}{3} \cdot L$ $H C l \left(a q\right)$ for stoichiometric equivalence.