(i) Barbeque is usually done in the open. In cold countries, although both propane and butane can be used but propane is preferred because it works better in low temperature. The reason being that due to lower boiling point (i.e., 231 K), propane always remains as a gas in the cylinder inspite of cooling produced by Joule Thomson effect during its use and thus ensures a constant supply of the gas. In contrast, butane due to its higher boiling point (272.5 K) and cooling produced by Joule - Thomson effect, it becomes a liquid in the cylinder and thus the supply of the gas becomes slower and slower as the gas is being used.
(ii) Butane is used in cigarette lighters since it can be easily liquefied at room temperature.
(iii) Mineral oil is a mixture of liquid alkanes containing 16-18 carbon atoms and is used as a laxative and as a lubricant.
(iv) Alkanes with 18 or more carbon atoms are waxy solids. These are used as waxy coatings on fruits and vegetables to help them retain moisture, inhibit mould growth and enhance appearance.
(v) Vaseline or petroleum jelly, is a mixture of solid alkanes having low melting points. It can prevent moisture loss and chapped lips and soften nail cuticles. It is also used in ointments and cosmetics.