Match the complex ions given in Column I with the colours given in Column II and assign the correct code

Column I (Complex ion)	Column II (Colour)
A. [Co(NH3)6]3+	1. Violet
B. [Ti(H2O)6]3+	2. Green
C. [Ni(H2O)6]2+	3. Pale blue
D. [Ni(H2O)4(en]2+ (aq)	4. Yellowish orange
	5. Blue

Code

(i) A (1)           B (2)          C (4)           D (5)

(ii) A (4)          B (3)          C (2)           D (1)

(iii) A (3)         B (2)          C (4)           D (1)

(iv) A (4)         B (1)          C (2)           D (3)

CoCl₃.NH₃ + AgNO₃ $\stackrel{}{\to }AgC\mathcal{l}\downarrow \left(2mol\right)$  

$\left[Co{\left(N{H}_3\right)}_{5}C\mathcal{l}\right]C{\mathcal{l}}_2+AgN{O}_3\stackrel{}{\to }AgC\mathcal{l}\downarrow \left(2mol\right)$  

x = 5

In H₂O (polar solvent) dibromophenol derivative and in CS₂ (non-polar solvent moneobromo phenol derivate is obtained.

3d => 4d => 5d CFSE increases for the same ligands.

Factual
⇒ leaching methods is used for those metal in which metal is more soluble than impurities and these are Al, Au, Ag, low grade Cu

σ bonded organometallic compound ⇒ M – C
σ-bond
and in π – bonded organo metallic compound
M – C
π bond
In ferrocene, there is π-bond