One mole of two different compounds happens to weight the same, but one compound ionizes in water and the other does not. Which will give the lowest freezing point depression?

1 Answer
Nov 27, 2016

The species that ionizes will give the GREATER freezing point depression.

Explanation:

A binary ionic species, #MX#, will give rise to two species in solution, i.e:

#MX(s) rarr M^(+)(aq) + X^(-)(aq)#

The ions are aquated by several water molecules, and are hence represented as #M^(+)(aq) #. And since #"freezing point depression"# is a colligative property that depends on the number of particles in solution, the binary salt will give TWICE the freezing point depression of a neutral solvate.