There are ten possible isomers of a compound with formula C₆H₁₂ that are optically active.

Explanation:

An Example Isomer:

A compound with the formula C₆H₁₂ that is optically active and has only one chiral center can be a hexane derivative with a substitution that creates one chiral carbon. To create such a chiral center, four different groups should be attached to a single carbon atom. A simple example of such an isomer can be a molecule of 3-methylpentane, where the second carbon atom (starting from either end of the carbon chain) is bonded to a methyl group, in addition to hydrogens and the remaining carbon chain, making this carbon the chiral center.

The structure can be represented as follows:

CH₃CH(CH₃)CH₂CH₂CH₂CH₃

Here, the second carbon from the left (or the fourth from the right) is chiral because it's attached to four different groups: a hydrogen atom, a methyl group, and two different alkyl chains (ethyl and propyl).

Enantiomers:

Enantiomers are optical isomers that are non-superimposable mirror images. Because they can rotate plane-polarized light in opposite directions, they are said to have optical activity. Given that a molecule has a single chiral center, it will exist as two enantiomers.