[mojo4king]

How would you go about calculating the carbon dioxide output per unit mass and volume for combustion products, i have already calculated the energy outputs per unit mass and volume.

Many thanks.

[mojo4king]

for eg. combustion of CH4:
CH4(g) + 2O2(g) ---> CO2(g) + 2H2O(l)

enthalpy of combustion: (-393.51) + 2(-241.82) - (-74.81) = -802.34 kj/mol

energy output per unit mass:
802.34 x 1000/16(molar mass) = -50146.25 kj/kg

energy output per unit volume:
-50146.25 x 0.645(mass density) = -32344.33 kj/m3

However I have no clue on how to calculate the carbon dioxide output per unit mass and volume, any help would be kindly appreciated.
Many thanks.

[mojo4king]

1 mole of CO2= 44g
1 mole of CH4= 16g
At STP the volume of an ideal gas occupies 0.0224 m3...

[mojo4king]

i need to work out the CO2 output per unit mass and volume,
the units would be kj/kg and kj/m3,correct?

the CO2 energy output per mass....
-802.34 kj/mol divided by 12 g/mol equals 66860 kj/kg

the CO2 energy output per unit volume:
66860 x 0.645 (CH4 mass density)= 43124.7 kj/m3

Have i done these calculations properly?
Thanks.

[enahs]

You say "calculate the carbon dioxide output per unit mass and volume of combustion product".
By that wording, it seems energy does not come into play.


The wording of that, implies to me, the amount of CO2 in mass and volume of the product created (I.E. How much CO2 relative to water).

Could you perhaps reread the question and post it exactly as worded. As I am confused as to why you are doing energy calculations.