for the reaction 2CH3CH2CH2CH3(g) + 13O2 --> 9CO2(g) +10H2O(g) delta h = -5285.0 kJ. a) how many kilojoules are released when 27.86 g of butane are burne? Assume that an excess of oxygen is present. b) if 327 J are released, how much butane was burned?