Answer to Question #162328 in General Chemistry for Akinola

Question

The standard heat of formation of methane,CO2&H2O are -76.2kj/mol,-398.8kj/mol&-241.6kj/mol. Calculate the heat evolved by burning 1m^3 of methane measured under normal condition (stp)
CH4 +CO2 — CO2 +2H20

Answer 1

For one mole of methane

∆H= H_p - H_R

∆H= [-398.8+2(-241.6)] - [-76.2]

∆H= -369.8KJ/mol

Volume of methane=1m³= 1000dm³

Since 1mol of methane at STP occupies 22.4dm³

22.4dm³ of methane yields -369.8KJ

1000dm³ of methane will yield

-369.8 x 1000/22.4 = -16509KJ