Question

${{C}_{n}}{{H}_{2n-2}}$ is the formula for

Answer 1

Hint: Hydrocarbons which have triple bonds in them have the formula of type ${{C}_{n}}{{H}_{2n-2}}$.
There are three types of hydrocarbons (molecules made up of carbon and hydrogen and they are covalently bonded):
Alkane
Alkene
Alkyne

Complete answer:
Alkanes are the type of hydrocarbons that have a single bond between the molecules. General molecular formula of alkanes is\[{{C}_{n}}~{{H}_{2n+2}}~\] in which n stands out for the number of carbon atoms. They only have sigma bonds in their compounds. Simplest example of alkane is ethane which has a molecular formula ${{C}_{2}}{{H}_{6}}$.
Alkanes are important raw materials of the chemical industry and the principal constituent of gasoline and lubricating oils. Natural gas mainly contains methane and ethane and is used for heating and cooking purposes and for power utilities (gas turbines).

Alkenes are the type of hydrocarbons that have double bonds in their compounds. They are unsaturated. General formula of the compounds of alkene are ${{C}_{n}}{{H}_{2n}}$ in which n stands for number of carbon atoms. Alkenes have 2 hydrogen less than corresponding alkanes. They have sigma as well as pi bonds in their compounds. Simplest example of alkene isothere which has a chemical formula ${{C}_{2}}{{H}_{4}}$ .

Alkynes are the type of hydrocarbons that are highly unsaturated. The general formula of the alkynes is${{C}_{n}}{{H}_{2n-2}}$. The compounds of alkynes consist of 2 pi bonds.
Alkynes have 4 hydrogen less than the corresponding alkane and 2 hydrogen less than corresponding alkene. They have 2 pi bonds in their compounds. Simplest example of alkyne is ethyne which has a chemical formula of ${{C}_{2}}{{H}_{2}}$.

Note: Alkynes are the type of hydrocarbons that have triple bonds in their compounds. They too are unsaturated. They can be represented by the general formula ${{C}_{n}}{{H}_{2n-2}}$ in which n stands for number of carbon atoms.