Which statement about the square planar complex [Pt(NH3)(py)ClBr] (py = pyridine) is correct?

It has 3 geometrical isomers, all diamagnetic and none optically active.

It has 3 geometrical isomers, all paramagnetic with two unpaired electrons.

It has 3 geometrical isomers, each of which exists as a pair of enantiomers.

It has 3 geometrical isomers, all diamagnetic and none optically active.

It has 2 geometrical isomers, one of which is optically active.

JEE Advanced levelSingle correct optionDifficulty 3 of 3cc163

Which statement about the square planar complex $[Pt (NH X_{3}) (py) ClBr]$ (py = pyridine) is correct?

Pt(II) is

d^{8}

and in a square planar field all electrons are paired, so every isomer is diamagnetic.

Mabcd

has 3 geometrical isomers. Each one is planar, so the molecular plane is a mirror plane, and none is optically active.