Fe3+ cation gives a Prussian blue precipitate on addition of potassium ferrocyanide solution due to the formation of:
- [Fe(H2O)6]2 [Fe(CN)6]
- Fe2[Fe(CN)6]2
- Fe3[Fe(OH)2 (CN)4]2
- Fe4[Fe(CN)6]3
The Correct Option is D
Solution and Explanation
Top Questions on coordination compounds
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Concepts Used:
Werner’s Theory of Coordination Compounds
In 1893 Werner produced a theory to explain the structures, formation and nature of bonding in the coordination compounds. This theory is known as Werner’s theory of coordination compounds.
Postulates of Werner's Theory:
The important postulates as observed by Alfred Werner throughout his experiments are as follows:
- The complex/ coordination compounds contain a central metal atom.
- The metal atoms in a coordination compound generally show two types of valency: primary valency and secondary valency.
- The primary valencies denote the oxidation state. They are ionizable and are satisfied by the negative ions.
- Secondary valencies denote the coordination number. They are non-ionizable and are fixed for every metal atom. The secondary valency is generally satisfied by the neutral molecules or negative ions.
- The metal atoms should satisfy both primary and secondary valencies.
- The secondary valency of the atom basically shows the geometry/ polyhedra of the particular coordination compound.
Limitations of Werner’s Theory:
- Though Werner explained some properties of the coordination compound, he failed to explain the colour of the coordinate compound.
- He could not explain the magnetic and optical properties of coordination compounds.
- He could not answer the question, why does the coordination sphere have a definite geometry.