notam amestecul m = 5 moli CH4 + n moli C2H6
1 mol CH4 ................... 890,2 kJ
5 moli .......................... q = 4451 kJ
10689 kJ - 4451 kJ = 6238 kJ
1 mol C2H6 ....................... 1559,5 kJ
n moli ................................... 6238 kJ
= 4 moli C2H6