Q. 495.0( 1 Vote )
The halides of transition elements become more covalent with increasing oxidation state of the metal. Why?
As the oxidation state increases, the charge on the atom increases and size of the ion of transition element decreases. Fajan’s rule’s states that greater the charge on an atom, greater the covalent character. So, halides become more covalent with increasing oxidation state.
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When a chromite ore (A) is fused with sodium carbonate in free excess of air and the product is dissolved in water, a yellow solution of compound (B) is obtained. After treatment of this yellow solution with sulphuric acid, compound (C) can be crystallised from the solution. When compound (C) is treated with KCl solution, orange crystals of compound (D) crystallise out. Identify compounds A to D and also explain the reactions.
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