2 моль                                    Х г

  C         +         O2       =       CO2

n = 1 моль                            n = 1 моль

                                             Mr = 44 г/моль

                                             m = 44 г

2 моль С    -    Х г СО2

1 моль С   -    44 г СО2

m(CO2) = 2 * 44 = 88 г