Match the solutions given in Column I with the colours given in Column II.

Column I
(Aqueous solution of salt)
Column II
(Colour)
A.  FeSO4 .7H2O 1. Green
B.  NiCl2 . 4H2O 2. Light pink
C.  MnCl2.4H2O 3. Blue
D.  CoCl2. 6H2O 4. Pale green

5. Pink

Codes:

A B C D
1. 2 3 4 1
2. 1 2 3 5
3. 5 4 3 2
4. 4 1 2 5
HINT: MnCl2 . 4H2O is light pink colour.
Explanation:
The d block complex shows colour because of the d-d transition.

      An aqueous solution of salt

                    Colour 

A. FeSO4 . 7H2O

Pale green

B. NiCl2 . 4H2O

Green

C. MnCl2 . 4H2O

Light pink

D. CoCl2 . 6H2O

Pink


Hence, option fourth is the correct answer.