A constant-volume tank contains a mixture of 1 lbmol of benzene (C₆H₆) gas and 60 percent excess air at 77°F and 1 atm. The contents of the tank are now ignited, and all the hydrogen in the fuel burns to H₂O but only 92 percent of the carbon burns to CO₂, the remaining 8 percent forming CO. If the final temperature in the tank is 2100 R, determine the heat transfer from the combustion chamber during this process.