Propane is usually sold in gallons, and natural gas in therms or cubic feet, so you’re stuck with a math problem if you want to compare them. The important thing is how much you pay for a given ...

The reason, he wrote, is that propane has a much higher boiling point (–44F at atmospheric pressure) than natural gas, or methane, (–260F at atmospheric pressure).

Stable isotope equilibria in the dihydrogen-water-methane-ethane-propane system. Part 2: Experimental determination of hydrogen isotopic equilibrium for ethane-H2 from 30-200 °C and propane-H2 ...