If a pork roast must absorb

1700kJ

to fully cook, and if only

11%

of the heat produced by the barbeque is actually absorbed by the roast, what mass of

CO

2

is emitted into the atmosphere during the grilling of the pork roast?

Let us assume propane was the fuel

C3H8 (g) + 5O2 (g) - - - > 3CO2 (g) + 4H2O (g) = 2217kJ

1 mole ofpropane produces 3 moles of CO2

heat absorbed by pork = 0.11 x 2217

= 243.87 kJ/mol

number of moles of propane = 1700kJ / 243.87 kJ/mol

= 6.971 moles

1 mole of C3H8 = 3 moles ofCO2

6.971 moles of C3H8 = ?

3 x 6.971 = 20.913 moles of CO2

Convert to grams

mass = MW x mole

= 44 x 20.913

= 920.172g of CO2 emitted