Question

What is an alkyl group?

Answer 1

Definition of the alkyl group:

• Functional group that has a carbon and hydrogen atom present in its structure
• An alkyl substituent is an alkane which is missing one hydrogen
• The "ane" suffix is replaced by "yl" in naming groups.
• The symbol R is used to designate a generic alkyl group.
• Alkanes can be described by the general formula${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+2}$. An alkyl group is formed by removing one hydrogen from the alkane chain and is described by the formula${\mathrm{C}}_{\mathrm{n}}{\mathrm{H}}_{2\mathrm{n}+1}$.
• $\underset{\mathrm{Methane}}{{\mathrm{CH}}_4}\to \underset{\mathrm{Methyl}}{{{\mathrm{CH}}_3}^{}}$ and $\underset{\mathrm{Propane}}{{\mathrm{CH}}_3{\mathrm{CH}}_2{\mathrm{CH}}_3}\to \underset{\mathrm{Propyl}}{{\mathrm{CH}}_3{\mathrm{CH}}_2{{\mathrm{CH}}_2}^{}}$

For example,

Alkane name	Alkane formula	Alkyl name	Alkyl formula
Ethane	${\mathrm{C}}_2{\mathrm{H}}_6$	Ethyl	$\underset{\mathrm{Ethane}}{{\mathrm{C}}_2{\mathrm{H}}_6}\to \underset{\mathrm{Ethyl}}{{{\mathrm{C}}_2{\mathrm{H}}_5}^{}}$
Butane	${\mathrm{C}}_4{\mathrm{H}}_{10}$	Butyl	$\underset{\mathrm{Butane}}{{\mathrm{C}}_4{\mathrm{H}}_{10}}\to \underset{\mathrm{Butyl}}{{{\mathrm{C}}_4{\mathrm{H}}_9}^{}}$