Which of the following statements are correct about stability of chelates ?

Options

A. As the no. of rings in complex increases, stability of chelate also increases
B. A chelate having five memberd ring on more stable if it contains double bonds
C. A chelate having six memberd ring in more stable if it does not contain double bonds
D. Chelating ligands are atleast bidentate ligands

Answer

A, D

Explanation

The more rings that are formed by the polydentate ligand in chelation, the more stable the complex is Eg.. EDTA forms five rings as is a hexadentate ligand. Its complexes with even `Ca^(2+)` ion are stable. Chelate compounds are more stable, if they posses alternate single and double bonds which would help delocalisation of electron cloud.