C + O2 = CO2 + Q
%C = m C/m cărbune * 100
m C = 2*60/100 = 1,2 t C = 1200 kg C
M C = 12 g/mol
12 g C................1 moli O2
1200 kg C..................x
x = 100 kmoli O2
n = m/M = 1200/12 = 100 kmoli C
1 mol C.........393 kJ
100 kmoli C...........y
x = 39300 kJ = 39,3 MJ (mega jouli)