Question

Chloride of fourth group cation in qualitative analysis gives a green coloured complex [a] in aqueous solution which when treated with ethane –1, 2 – diamine (en) gives pale - yellow solution [b] which on subsequent addition of ethane –1, 2 – diamine turns to blue/purple [c] and finally to violet [d]. write the structures of complexes [a], [b], [c] and [d].

Answer 1

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Chloride of fourth group cation in qualitative analysis gives a green coloured complex [A] in aqueous solution which when treated with ethane –1, 2 – diamine (en) gives pale - yellow solution [B] which on subsequent addition of ethane –1, 2 – diamine turns to blue/purple [C] and finally to violet [D]

A is [Ni(H₂O)₆]²⁺

B= [Ni(H₂O)₄(en)]²⁺

C= [Ni(H₂O)₂(en)₂]²⁺

D= [Ni(en)₃]²⁺