The combustion reaction of 0.148 g of a hydrocarbon
having formula CnH2n + 2 with an excess of O2 in a 400.0 mL steel
container. Before reaction, the gaseous mixture had a temperature of 25.0 °C and a pressure of 2.000 atm. After complete combustion and loss of considerable heat, the mixture of products
and excess O2 had a temperature of 125.0 °C and a pressure of
What is the formula and molar mass of the hydrocarbon?