Kimia

ΔH reaksi = ∑ energi reaksi -∑ energi ikatan produk.

                = [(4 mol C-H+2 mol o2o)-(2 mol C₂O+4 mol O-H)] KJ

                = [(1.652 KJ + 990 KJ)-(1.598 KJ+1.852 KJ)]

                = 2.642 KJ – 3.450 KJ

                = -808 KJ.