Anhydrous cobalt(II) chloride is blue in blue in colour but on dissolving in water it changes to pink in colour because

Options

A. its oxidation state changes
B. Its magnetic character changes
C. its coordination number changes
D. in water it shows fluorescence

Answer

c

Explanation

`Co^(II)Cl_2` has a blue colour in tetrahedral geometry. It changes to pink in colour with the change in coordination number to six.