The complex [Pt(Py)(NH3)BrCl] will have how many geometrical isomers?
3
The complex is square planar and shows two cis and one trans isomers.
There are 4 ligands. This reduces to a problem of circular permutation such that we count only the sequence in which atoms are connected. Meaning, we disregard the direction - clockwise or counter-clockwise. The answer should be (n−1)!2 = 62 = 3. So we get 3 geometric isomers.