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Question
Define molality.
Solution
Molality (m) is defined as the number of moles of the solute dissolved in one kilogram (Kg) of the solvent. The units of molality are moles per kilogram, i.e., mole kg-1. The molality is preferred over molarity if the volume of the solution is either expanding or contracting with temperature.
molality (m) = `"Number of mole of solute"/"mass of solvent (in kg)"`
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