Question

Which of the following solutions has maximum freezing point depression at equimolal concentration?

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

Answer 1

Answer: (A)

$\left[\right.Co\left(\right.H_{2}O\left(\left.\right)_{6}\left]\right.Cl_{3} \rightarrow \left[\right.Co\left(\right.H_{2}O\left(\left.\right)_{6}\left(\left]\right.\right)^{3 +}+3Cl^{-}$
The complex gives maximum number of ions, hence its depression in freezing point will also be maximum as i is maximum (i = 4)