While both propane and butane are hydrocarbon gases, propane has the chemical formula C3H8, while butane has the chemical formula C4H10. Propane has a boiling point of approximately minus 44 degrees Fahrenheit, while butane has a boiling point of 30 to 34 degrees Fahrenheit, making propane more useful as a fuel in colder weather.Continue Reading
Butane and propane are both odorless, colorless gases. Compressing the gases converts them into a liquid that is easily stored and transported in pressurized tanks. In rural areas, residents often use a mixture of the two gases, known as liquefied petroleum gas, as fuel for heating and cooking. Campers use small canisters of LP gas to operate stoves, lights and grills. The design of some automobiles allows them to operate using LP gas as a fuel. In the United States, LP gas is at least 90 percent propane with the remaining 10 percent composed of butane, ethylene and propylene. Manufacturers add ethyl mercaptan as an odorant to allow users to detect possible gas leaks.
Both propane and butane are relatively clean burning with properly adjusted burners and an adequate oxygen supply. The by-products of burning these gases are carbon dioxide and water. However, if the oxygen is limited or the burner not adjusted correctly, the flame produces soot, a form of carbon, and carbon monoxide, a deadly yet odorless gas.Learn more about Chemistry