If the freezing point of a `0.01` molal aqueous solution of a cobalt (III) chloride-ammonia complex (which behaves as a strong electrolyte) is `-0.0558^(@)C`, the number of chloride (s) in the coordination sphere of the complex if `[K_(f)` of water `=1.86 K kg mol^(-1)]`

Answer

1

Explanation

`Delta T_(f) = I K_(f) m`
Given m = 0 .01 molal `Delta T_(f) = 0 - (0.0558^(@)) = 0.0558^(@)C`
`k_(f) = 1.86 K kg mol^(-1)`
`I = (Delta T_(f))/(k_(f) xx m) = (0.0558)/(1.86 xx 0.01) = 3`
Since three ions are produced by the complex , the molecular formual of the complex is `[Co(NH_(3))_(5)Cl]Cl_(2)` .
Thus, the number of `Cl^(-1)` ions in the coordination sphere is only one .