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Question
In comparison to a 0.01 m solution of glucose, the depression in freezing point of a 0.01 m MgCl2 solution is ______.
Options
the same
about twice
about three times
about six times
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Solution
In comparison to a 0.01 m solution of glucose, the depression in freezing point of a 0.01 m MgCl2 solution is about three times.
Explanation:
0.01 m solution of glucose does not ionize while 0.01 m MgCl2 solution furnishes 3 ions \[\ce{(Mg^{2+} + 2Cl^-)}\] in the solution, hence the value of colligative property for MgCl2 solution is about 3 times.
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