An aqueous solution of CoCl2 on addition of excess of cone. HCl turns blue due to the formation of

Question

An aqueous solution of CoCl2 on addition of excess of cone. HCl turns blue due to the formation of (A)  [Co(H2O)]Cl2 (B) .[ Co ( H 2 O )2] Cl 4]2- (C) [ CoCl 4]2- (D) [ Co ( H 2 O )2 Cl 2]

Tardigrade Admin · Accepted Answer

CoCl 2, a weak Lewis acid, reacts with chloride ion to produce salt containing the tetrahedral, [ CoCl 4]2- ion. It is blue when anhydrous and a deep magenta colour when hydrared, for this reason it is widely used as an indicator for water.

Q. An aqueous solution of $C o C l_{2}$ on addition of excess of cone. $H Cl$ turns blue due to the formation of

$[C o (H_{2} O)] C l_{2}$

$[C o (H_{2} O)_{2}] C l_{4}]^{2 -}$

$[C o C l_{4}]^{2 -}$

$[C o (H_{2} O)_{2} C l_{2}]$

$C o C l_{2}$ , a weak Lewis acid, reacts with chloride ion to produce salt containing the tetrahedral, $[C o C l_{4}]^{2 -}$ ion. It is blue when anhydrous and a deep magenta colour when hydrared, for this reason it is widely used as an indicator for water.

Q. An aqueous solution of CoCl2​ on addition of excess of cone. HCl turns blue due to the formation of

[Co(H2​O)]Cl2​

[Co(H2​O)2​]Cl4​]2−

[CoCl4​]2−

[Co(H2​O)2​Cl2​]