Question

State physical properties of alkanes.​

Answer 1

Answer : -

Physical properties of alkanes :

(1) Alkanes are colourless and odourless.

(2) At room temperature, first four alkanes $\sf{C_1\:, \:to \:C_4}$ are gases, $\sf{C_5\:, \:to \:C_{17}}$, are liquids and higher alkanes $\sf{C_{18}}$ onwards are solids.

(3) Alkanes are insoluble in water but dissolve in non-polar solvents like benzene, ether, chloroform, etc.

(4) The branched chain alkanes have lower boiling points than straight chain alkanes. As the branches in alkanes increase, the boiling point lowers, because then the surface area decreases resulting in weaker intermolecular forces.

Answer 2

Answer:

Explanation:

Alkanes are colourless.

Alkanes are less dense than water (alkanes float on top of water).

Alkanes are non-polar molecules so they are more soluble in non-polar solvents than they are in polar solvents.