determine the enthalphy of combustion of CH4 at 298 K if the following is given C+O2=CO2 ; delta H=-393,H2+1+2(O2)=H2O;delta - Chemistry - Thermodynamics and Thermochemistry

Question

​​determine the enthalphy of combustion of CH4 at 298 K
if the following is given C+O2=CO2 ; delta
H=-393,H2+1+2(O2)=H2O;delta H=-285 8, CO2+2H2O=CH4+2O2;deltaH=890 3

Akanksha C. · Accepted Answer

Dear Student,

Heat of combustion of methane = [heat of formation of
CO2 (g) + 2 x heat of formation of H2O (g)] -
[heat of formation of CH4 (g) + 2 x heat of formation of
O2 (g)]

Heat of combustion = [ -393 5 + 2 X (-285 8)] - [ 890 3 + 2 X
0]

Heat of combustion = -393 5 -571 6 - 890 3

Heat of combustion = -1855 4 Kj/mol

Kindly check the value of heat of formation of CH4 once
again as it should -74 8 instead of 890 3 Kj/mol

Regards

​​determine the enthalphy of combustion of CH4 at 298 K if the following is given C+O2=CO2 ; delta H=-393,H2+1+2(O2)=H2O;delta H=-285.8, CO2+2H2O=CH4+2O2;deltaH=890.3

determine the enthalphy of combustion of CH4 at 298 K if the following is given C+O2=CO2 ; delta H=-393,H2+1+2(O2)=H2O;delta H=-285.8, CO2+2H2O=CH4+2O2;deltaH=890.3