Polydentate molecules

[claire smith]

A textbook question asks: Which of the ligands can be polydentate? If the ligand can be polydentate, give the maximum number of places on the ligand that can bind simultaneously to a single metal center.

I'm a little confused on the process of how you would start to figure this out. Thanks!

[Anna Hilger 3H]

Hi,
A polydentate ligand has at least two sites (donates 2+ electrons PR) that the ligand can bind at (at least two bonds are made)--it is an atom with 1+ lone pairs. So, you want to look at lone pairs on the ligands.
Hope this helps :)

[Rose Arcallana 2B]

Could you put the book number to be more specific?

But from the info you gave, I would start with determining how many bonds that specific ligand can do. A polydentate is a ligand that can make +2 bonds, so I would look at each ligand and check if they at least can do 2 bonds. By bonds I mean those with a "-" charge like CN-1, considering ligands are electron donators, but also look for ones that are polar because even if they are neutral they can still donate e- like NH3. :)