Answer the following case-based question given below:
The compounds which have the same molecular formula but differ from each other in physical or chemical properties are called isomers and the phenomenon is called isomerism.
When the isomerism is due to difference in the arrangement of atoms within the molecule, without any reference to space, the phenomenon is called structural isomerism.
In other words, structural isomers are compounds that have the same molecular formula but different structural formulas, i.e., they are different in the order in which different atoms are linked.
In these compounds, carbon atoms can be linked together in the form of straight chains, branched chains or even rings.
a. Which of the following sets of compounds have same molecular formula?
b. In order to form branching, an organic compound must have a minimum of
c. The number of isomers of pentane is
d. The number of isomers of butane is