Question

What is the difference between isopentane and neopentane structures?
A.) Iso has one $\text{C}{{\text{H}}_{\text{3}}}$ group and neo has two $\text{C}{{\text{H}}_{\text{3}}}$ on the C atom next to end C atom.
B.) lso has two $\text{C}{{\text{H}}_{\text{3}}}$ group and neo has two $\text{C}{{\text{H}}_{\text{3}}}$ on the C atom next to end C atom.
C.) Iso has two $\text{C}{{\text{H}}_{\text{3}}}$ group and neo has three $\text{C}{{\text{H}}_{\text{3}}}$ on the C atom next to end C atom
D.) None of the above.

Answer 1

Hint: We know that isopentane contains a four-membered carbon chain while neopentane contains one carbon centre attached with four methyl groups. Knowing this fact we can solve the following question.

Complete step-by-step answer:

Isopentane is a compound having 5 carbon atoms with only a single branched chain. Neopentane is a compound which has 5 carbon atoms with two or more than two branched chains. The difference between isopentane and neopentane structure is that isopentane consists of a four-membered carbon chain with a single methyl group that was attached to this chain at the second carbon atom. On the other hand, neopentane contains four methyl groups attached to a carbon atom at its centre.


Isopentane
Neopentane Therefore, the answer does not match any of the given options.

Hence, the correct option is Option D.

Note: We know that isopentane and neopentane both are an organic compound having the chemical formula ${{\text{C}}_{\text{5}}}{{\text{H}}_{\text{12}}}$. Isopentane exists as a colourless liquid while Neopentane exists as a colourless gas, at standard temperature and pressure. The IUPAC name of Isopentane is 2-Methylbutane whereas the IUPAC name of Neopentane is 2,2-Dimethylpropane. The molar mass of Isopentane is \[\text{72}\text{.15 g/mol}\] and its melting point is \[\text{-161 }\!\!{}^\circ\!\!\text{ C to 159 }\!\!{}^\circ\!\!\text{ C}\] and its boiling point ranges from \[\text{27}\text{.8}{}^\circ \text{C to 28}\text{.2}{}^\circ \text{C}\]. Neopentane is a highly volatile liquid and its melting point is \[\text{-16}\text{.5 }\!\!{}^\circ\!\!\text{ C}\] and its boiling point is \[\text{9}\text{.5 }\!\!{}^\circ\!\!\text{ C}\].