Question

If excess of $AgNO_{3}$ solution is added to $100 \,mL$ of a $0.024 \,M$ solution of dichlorobis (ethylenediamine) cobalt (III) chloride, how many moles of $AgCl$ be precipitated?

• A. $0.0012$
• B. $0.0016$
• C. $0.0024$
• D. $0.0048$

Answer 1

Answer: (C)

$Co^{3+} + 2Cl^{-} + 2 (en)$
net charge =$ +1$
$[Co(en)_{2}Cl_{2}]^{+}Cl^{-} \to [Co(en)_{2}Cl_{2}]^{+} + Cl^{-}$
Only one $Cl^{-}$ which is precipitated as $AgCl$
$100\, mL$ of $0.024 \,M$ complex = $2.4$ millimol = $0.0024$ mol