Question

What are structural isomers? Name the first member of alkanes that shows structural isomerism.

Answer 1

Hint: A structural isomer of a compound (also known as a constitutional isomer in IUPAC terminology) is a compound having the same number of atoms of each element but logically different bonds between them. Previously, the word "metamer" was used to describe the same idea.

Complete answer:
A structural isomer, also known as a constitutional isomer, is an organic molecule that has the same chemical formula but differs in structure. The most extreme kind of isomerism is structural isomerism. It differs from stereoisomerism, which has the identical atoms and bonding system but a distinct relative spatial arrangement of the atoms. Differences between isotopes of the same element are generally overlooked. In other cases, however, distinct isotopes of the same element may be treated as separate elements. In the second example, structural isotopomers are two molecules with the same number of atoms of each isotope but different bonding schemes.
Butane is the first member of alkanes that shows structural isomerism.
Both molecules must have the same molecular formula, but the atom arrangement must be different. Take a look at the structures of n-butane and isobutane, for example. $C_4{H}_{10}$ is the same chemical formula for each of these compounds. Atomic connection is the ability of atoms to communicate with one another (carbon atoms). In the case of n-butane, all carbon atoms are in a straight chain, but there is a side chain in the case of isobutane. As a result, they have distinct atom connections and are constitutional isomers of one another.

Note:
Compounds with the same molecular formula but distinct structural formulae are known as constitutional isomers. In other words, constitutional isomers differ in the way atoms in molecules are connected. We must count the number of each atom in each molecule to determine whether they are constitutional isomers of each other.