`[CoCl_(2)(en)_(2)]^(+)` has three isomers. How can these be identified using physical methods?

Explanation

The given compounds has one trans-and two cis-isomers. The trans - isomer is optically inactive (optical rotation = 0 ). The cis - isomers are optically active and they bear enantiomeric relationship to each other i.e., they rotate the plane of polarised light to the same extent but in opposite directions. These compounds can be identified by measuring their optical rotation using a polarimeter.