### carbon dioxide output??

Posted:

**Sat Aug 25, 2007 6:07 am**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

1 mole of CO2= 44g

1 mole of CH4= 16g

At STP the volume of an ideal gas occupies 0.0224 m3...

the CO2 energy output per mass....

-802.34 kj/mol divided by 12 g/mol equals 66.86 kj/g

am i doing the right thing, and how would you calculate the CO2 output per unit volume?

Many thanks.

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

1 mole of CO2= 44g

1 mole of CH4= 16g

At STP the volume of an ideal gas occupies 0.0224 m3...

the CO2 energy output per mass....

-802.34 kj/mol divided by 12 g/mol equals 66.86 kj/g

am i doing the right thing, and how would you calculate the CO2 output per unit volume?

Many thanks.