When 1 mole of CrCl3.6H2O is treated with excess of AgNO3, 3 moles of AgCl are obtained. The formula of the complex is
(a) [CrCl3(H2O)3]3H2O
(b) [CrCl3(H2O)4]Cl2.2H2O
(c) [CrCl3(H2O)5]Cl2.H2O
(d) [Cr(H2O)6]Cl3
1 mole of AgNO3 precipiates one free chloride ion (Cl−.)
Here, 3 moles of AgCl are precipitated by excess of AgNO3. Hence, there must be three free Cl− ions.
So, the formula of the complex can be [Cr(H2O)6]Cl3 and the correct choice is (d).