I encountered this question in my country's Chemistry textbook of class 12. No solutions are published, but the answer given at the back states - "There are 10 possible isomers. (Hint: There are geometrical, ionisation and linkage isomers possible)"

I think the answer should be 9 by considering geometrical, ionisation, linkage and solvate isomerism.

Recently a problem came in the JEE Advanced Examination (entrance exam for admissions into the IITs) Paper 1 Chemistry section

enter image description here

Complex is [Pt(NH3)4Cl2]Br2

What should be the correct answer? Do we consider solvate isomerism with NH3 outside the coordination sphere?

  • $\begingroup$ Out of curiosity: Do you just have to write down the number, or can you write a few lines with your reasoning? $\endgroup$
    – Karl
    Oct 7 at 11:11
  • $\begingroup$ You can write down the number with some reasoning and preferably a good source/paper if possible. In the exam we had to just report the answer as an integer $\endgroup$
    – Anonymous
    Oct 7 at 11:14
  • $\begingroup$ And if you wrote "9" and they expect "10", you get zero points. Your reasoning will not be taken into account? $\endgroup$
    – Karl
    Oct 7 at 11:36
  • $\begingroup$ Yes we get 0 points if our answer is not as they expect. They don't ask for any reasoning. $\endgroup$
    – Anonymous
    Oct 7 at 11:52
  • $\begingroup$ So they're testing your status of brainwashery, no actual chemistry knowledge. ;-) OK, that's actually sad. $\endgroup$
    – Karl
    Oct 7 at 15:15