Question

Match the following alkanes with their physical state of existence at room temperature.

• A. Solid
• B. Liquid
• C. Gas

Answer 1

Lower alkanes, up to 5 carbon atoms in a chain, have a very small magnitude of Van der Waals forces because the surface area of compounds is low. Thus they exist as gases at room temperature. Alkanes with 6 to 18 carbon atoms in a chain exist as liquids as the magnitude of force increases with increasing surface area. Beyond 18 carbon atoms, the magnitude of force becomes very high and those alkanes exist as solids at room temperature.