Х г                                       11,2 л

  Zn        +      2HCl    =      ZnCl2       +     H2

                   n = 2 моль                           n = 1 моль

                  Mr = 36 г/моль                    Vm=22,4 л/моль

                 m = 72 г                                 V = 22,4 л

Х г HCl    -    11,2 л Н2

72 г HCl   -    22,4 л Н2

m(HCl) = 72 * 11,2 / 22,4 = 36 г