Question

The anion of acetylacetone (acac) forms Co(acac)₃ chelate with Co³⁺. The rings of the chelate are
(a) three membered
(b) five membered
(c) four membered
(d) six membered

Answer 1

Answer:

The anion of acetylacetone (acac) forms Co(acac)₃ chelate with Co³⁺ and forms a six member chelate ring. (d)

Explanation:

This reaction wherein the acetylacetone forms a ring structure is called tautomerism. In this reaction, the keto-form of the acetylacetone is more dominent in the liquid form but in gaseous form, the two tautomers co-exist in an equilibrium,The keto and enol tautomers of acetylacetone coexist in solution. Hence, the chelate formed, is between 6 atoms, hence it is a six member chelate ring.