Are alkanes liquid at room temperature?

1 Answer
Apr 12, 2016

Absolutely not! Some are, but methane is a room temperature gas.

Explanation:

The physical state of an alkane (of ANY substance) depends on the degree of intermolecular force. Small chain alkanes have minimal degrees of intermolecular attraction. They are thus gases. As the chain gets longer, intermolecular attraction becomes greater and liquids can be obtained at normal temperature and pressures. From memory, butane, #n-C_4H_10# has a boiling point of approx. #0# #""^@#, whereas n-hexane has a boiling point of approx. #69# #""^@#.

As the carbon chain gets very long, the physical state of the alkane becomes oily and waxy, but even #n-C_10H_24# is a room temperature liquid.