$q_v^{\text{'}}=(c_{v{m}_{CO2}}{|}_0^{t2}*r_{CO2}+c_{v{m}_{H2O}}^{\text{'}}{|}_0^{t2}*r_{H2O}+c_{v{m}_{O2}}^{\text{'}}{|}_0^{t2}*r_{O2}+c_{v{m}_{N2}}^{\text{'}}{|}_0^{t2}*r_{N2})*t_2-$

$-(c_{v{m}_{CO2}}^{\text{'}}{|}_0^{t1}*r_{CO2}+c_{v{m}_{H2O}}^{\text{'}}{|}_0^{t1}*r_{H2O}+c_{v{m}_{O2}}^{\text{'}}{|}_0^{t1}*r_{O2}+c_{v{m}_{N2}}^{\text{'}}{|}_0^{t1}*r_{N2})*t_1=$

$=(1,5587*0,12+1,1945*0,07+1,0065*0,05+0,9496*0,76)*400-$

$-(1,90585*0,12+1,4189*0,07+1,1346*0,05+1,0545*0,76)*1250=$

$=-1071k\frac{J}{m^3}.$