______C2H6 + ______O2 --> ______CO2 + _______H2O
Calculate the mass of carbon dioxide formed when 7.80 g of benzene (C2H6) burns.
C2H6 + 5O2 --> 2CO2 + 6H2O
Molar mass of benzene = 78 g/mol
Mole benzene = 7.8 g/78 g/mol = 0.1 mol
From balanced equation, 2 moles of benzene burn in O2 to form 12 moles of CO2.
Therefore, 0.1 mol of benzene burns in O2 to form (12/2) x 0.1 = 0.6 mol of CO2.
Molar mass of CO2 = 44 g/mol
Hence, mass of CO2 formed = 0.6 mol x 44 g/mol = 26.4 g