Question

Many home barbeques are fueled with propane gas (C3H8).

What mass of carbon dioxide (in kg) is produced upon the complete combustion of 18.9 L of propane (approximate contents of one 5-gallon tank)? Assume that the density of the liquid propane in the tank is 0.621 g/mL. (Hint: Begin by writing a balanced equation for the combustion reaction.)

m = ______________kg

Answer 1

Given volume of the propane is , V = 18.9 L = 18.9x1000 mL

         density of the propaneis , d = 0.621 g/mL

So mass of propane , m = density x volume

                                      = 0.621 x 18.9x1000 g

                                      = 11736.9 g

The balanced Equation of combustion of propane is

        C₃H₈ + 5O₂ 3CO₂ + 4H₂O

Molarmass of propane,C₃H₈ is = (3xAt.mass of C ) + ( 8xAt.mass of H )

                                                = ( 3x12) + ( 8x1)

                                               = 44 g/mol

MOlar mass of carbon dioxide ,CO₂ is = At.mass of C + (2xAt.mass of O)

                                                             = 12 + (2x16)

                                                            = 44 g/mol

According to the balanced Equation ,

1 mole of propane produces 3 moles of CO₂

                                  OR

44 g of propane produces 3x44 g of CO₂

11736.9 g of propane produces 3x11736.9 g of CO₂

                                                    = 35210.7 g

                                                   = 35.2 kg                 Since 1 kg = 1000 g

So the mass of carbon dioxide is produced upon the complete combustion of propane is 35.2 kg