How do you classify alkanes, alkenes and alkynes?

Hint: In order to answer the question, to describe the classification of alkanes, alkenes and alkynes, on the basis of their general formula and the type of their carbon-carbon bond. We will discuss more about their classification.

Complete step by step solution:
They all three are classified on the basis of their general molecular formula-
(i) Alkanes:- The general formula of alkanes is $ {C_n}{H_{2n + 1}} $ . An alkane consists of hydrogen and carbon atoms arranged in a tree structure in which all the carbon–carbon bonds are single.
(ii) Alkenes:- The general formula of alkanes is $ {C_n}{H_{2n}} $ . Alkenes are acyclic (branched or unbranched) hydrocarbons having one carbon-to-carbon double bond $ \left( {C = C} \right) $ . Because alkenes contain less than the maximum possible number of hydrogen atoms per carbon atom, they are said to be unsaturated.
(iii) Alkynes:- The general formula of alkanes is $ {C_n}{H_{2n - 2}} $ . An alkyne is an unsaturated hydrocarbon containing at least one carbon—carbon triple bond. The simplest acyclic alkynes with only one triple bond and no other functional groups form a homologous series.

Note:
Other alkenes are formed in a similar way. Hydrocarbons having at least one triple bond between two carbon atoms are known as alkyne. $ \left( {Alkane{\text{ }}-{\text{ }}ane{\text{ }} + {\text{ }}yne{\text{ }} = {\text{ }}Alkyne} \right) $ . Similarly; General formula of alkyne is $ {C_n}{H_{2n - 2}} $ . As in the case of alkene, minimum two carbon atoms are required to form alkyne.