What are compounds that have the same molecular formula but different structural formulas called?
isotopes?
Compounds that have the same molecular formula but different structural formulas are called isomers. Isomers occur when the atoms in a compound are arranged differently, resulting in distinct structural and chemical properties. There are two types of isomers: structural isomers and stereoisomers.
Structural isomers have different connectivity among atoms. They differ in how the atoms are bonded to one another, leading to different structural arrangements. For example, consider the molecular formula C4H10. This molecular formula can correspond to two structurally different isomers: butane and 2-methylpropane. In butane, all carbon atoms are in a straight chain, while in 2-methylpropane, there is a branching of the chain due to the presence of a methyl group.
On the other hand, stereoisomers have the same connectivity among atoms but differ in their spatial arrangement. This can occur due to restricted rotation around a double bond or due to the presence of chiral centers. An example of stereoisomers is the compound 2-chlorobutane, which can exist as a pair of enantiomers (non-superimposable mirror images) due to the presence of a chiral carbon atom.
In summary, compounds with the same molecular formula but different structural formulas are called isomers, which can be further classified into structural isomers and stereoisomers.