Coal burns according to the reaction C + O2 ( CO2. The heat of combustion is 3.3 ( 107 J/kg of atomic carbon consumed.
(a) Express this in terms of energy per carbon atom.
(b) Express it in terms of energy per kilogram of the initial reactants, carbon and oxygen. (c) Suppose that the Sun (mass = 2.0 ( 1030 kg) were made of carbon and oxygen in combustible proportions and that it continued to radiate energy at its present rate of 3.9 ( 1026 W. How long would the Sun last?