# Question #2d9ce

Oct 28, 2016

I did not understand the wording of the question. I present here a solution assuming that the volume of HCl is asked for.

The balanced equation of the reaction ocurring in this case:

$C a C {O}_{3} \left(s\right) + 2 H C l \left(a q\right) \to C a C {l}_{2} \left(a q\right) + C {O}_{2} \left(g\right) + {H}_{2} O$

By this equation we see that 1mol $C a C {O}_{3}$ reacts with 2moles HCl to produce 1 mole $C {O}_{2}$

So
0.4mol $C a C {O}_{3}$ reacts with 0.8moles HCl to produce 0.4 mole $C {O}_{2}$

The strength of supplied HCl solution is 3M.
So to have 0.8mol HCl we require $0.8 m o l \times \frac{1}{3 \frac{\text{mol}}{L}} \approx 0.27 L$solution