Problem: It is often argued that natural gas (CH4) is preferred to petroleum (which we will approximate as isooctane, C8H18) in generating energy in that it produces less CO 2. The balanced  combustion reactions for CH4 and C8H18  are given below. CH4(g)  +  2O2(g)  →  CO2(g)  +   2H2O(g) 2C8H18(g)  +  25O2(g)  →  16CO2(g)  +   18H2O(g) Using the following heats of formation, calculate Joules of energy generated per mole of CO2 produced for each combustion. Is methane better than petroleum in lowering CO2 production (in other words, does it produce more CO2 per joules of energy)? H2O(g)       ΔH°f = -241.83 kJ/mol                CO2(g)       ΔH°f = -395.51 kJ/mol CH4(g)       ΔH°f = -74.1 kJ/mol                    C8H18(g)   ΔH°f = -224.1 kJ/mol  

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It is often argued that natural gas (CH4) is preferred to petroleum (which we will approximate as isooctane, C8H18) in generating energy in that it produces less CO 2. The balanced  combustion reactions for CH4 and C8H18  are given below.

CH4(g)  +  2O2(g)    CO2(g)  +   2H2O(g)

2C8H18(g)  +  25O2(g)    16CO2(g)  +   18H2O(g)

Using the following heats of formation, calculate Joules of energy generated per mole of CO2 produced for each combustion. Is methane better than petroleum in lowering CO2 production (in other words, does it produce more CO2 per joules of energy)?

H2O(g)       ΔH°f = -241.83 kJ/mol               

CO2(g)       ΔH°f = -395.51 kJ/mol

CH4(g)       ΔH°= -74.1 kJ/mol                   

C8H18(g)   ΔH°f = -224.1 kJ/mol

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