Question

The aqueous solution containing one mole of $CoCl_{3}.5NH_{3}$ consumed 2 mol of silver nitrate solution for precipitation of free chloride ions. The formula of the compound should be

• A. $\left[ Co \left( NH _{3}\right)_{5} Cl \right] Cl _{2}$
• B. $\left[ Co \left( NH _{3}\right)_{6} Cl _{2}\right] Cl$
• C. $\left[ Co \left( NH _{3}\right)_{4} Cl _{3}\right] NH _{3}$
• D. $\left[ Co \left( NH _{3}\right)_{5} Cl _{3}\right]$

Answer 1

Answer: (A)

Consumption of 2 mol of $AgNO_{3}$ indicates presence of 2 ionisable chloride ions per molecule. Hence the formula is $\left[ Co \left( NH _{3}\right)_{5} Cl \right] Cl _{2}$