A gaseous solution of methane and propane having a mass of 4.00 gg was burned in excess oxygen. Twenty-five percent of the heat produced was used to raise the temperature of 116 g g of liquid water from 0.0 CC to its boiling point at 100.0 C. What is the mass of methane in the mixture? (combHcombH for methane -802.5 kJmol1kJmol1 and for propane -2043.9 kJmol1kJmol1).