Number of possible isomers for the complex [Co(en)₂Cl₂]Cl (en: ethylenediamine) is:

Number of possible isomers for the complex [Co(en)₂Cl₂]Cl will be (en=ethylenediamine) 3. There are two geometrical isomers cis and trans. The trans isomer is optically inactive whereas the cis form exists in d and l forms.