Chapter 12, Problem 12.101SP

(a)

Interpretation Introduction

To determine:

Molality is present in case of elevation depression in temperature of a solution whereas, molarity in case of osmotic pressure.

EXPLAINATION:

In case of osmotic pressure the volume changes as a result of pressure variations
and volume change leads to change in concentration. As a necessity we deal with
concentrations expressed in terms of molarity.
In case of freezing point depression or boiling point elevation we talk about the
number of ions present in the solution as there is no volume change and molal
values of concentration can be taken into account as the elevation and depression
depend upon the change in number of species which is expressed by molality
values.

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