Question

Identify the following alkyl group from the expanded structure below:

• A. n-butyl
• B. n-pentyl
• C. iso-hexyl
• D. neo-heptyl

Answer 1

The correct option is B n-pentyl

The above structure is obtained by removing one $H$ atom from Pentane molecule.
So (b) is the correct option


Theory :
Alkyl groups :
The univalent groups obtained by the removal of one H atom from molecule of alkane
$C_n{H}_{2n+2}\stackrel{-H}{⟶}{C}_n{H}_{2n+1}$
$AlkaneAlkyl$
Atoms or groups of atoms which possess free valency are called “groups”.If there are two groups with the same molecular formula, then certain terms (prefixes) are used to differentiate them
'yl' substitutes for 'ane' in corresponding alkane
$\text{Name}\text{Mol.Formula}$
$\text{Methyl}-C{H}_3$
$\text{Ethyl}-C_2{H}_5$
$\text{Propyl}-C_3{H}_7$
$\text{Butyl}-C_4{H}_9$
$\text{Pentyl}-C_5{H}_{11}$
$\text{Hexyl}-C_6{H}_{13}$
$\text{Heptyl}-C_7{H}_{15}$
$\text{Octyl}-C_8{H}_{17}$
$\text{Nonyl}-C_9{H}_{19}$
$\text{Decyl}-C_{10}{H}_{21}$