Coordination Compounds Question 16
Question 16 - 31 January - Shift 1
Cobalt chloride when dissolved in water forms pink colored complex $X$ which has octahedral geometry. This solution on treating with cone $HCl$ forms deep blue complex, $Y$ which has a Z geometry. $X, Y$ and $Z$, respectively, are
(1) $X=[Co(H_2 O)_6]^{2+}, Y=[CoCl_4]^{2-}, Z=$ Tetrahedral
(2) $X=[Co(H_2 O_6)]^{2+}, Y=[CoCl_6]^{3-}, Z=$ Octahedral
(3) $X=[Co(H_2 O)_6]^{3+}, Y=[CoCl_6]^{3-}, Z=$ Octahedral
(4) $X=[Co(H_2 O)_4 Cl_2]^{+}, Y=[CoCl_4]^{2-}, Z=$ Tetrahedral
Show Answer
Answer: (1)
Solution:
Formula: VBT
$X= [Co(H_2 O)_6]^{+2}$ , Y = $[CoCl_4]^{2-}$ , Z = Tetrahedral
$CoCl_2+6 H_2 O \longrightarrow[Co(H_2 O)_6] Cl_2$
Pink(X)
octahedral
$\downarrow +HCl$ (conc.)
$[CoCl_4]^{2-}$
(Y)Blue solution
(Z)Tetrahedral
