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Question
Define the following modes of expressing the concentration of a solution. Which of these modes are independent of temperature and why?
m (Molality)
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Solution
The no. of moles of solute per kg of solvent
Molality (m) = `"Moles of solute"/"Mass of solvent in kg"`
Effect of temperature: Mass % ppm, mole fraction and molality do not change with temperature where as molarity, volume percentage and mass by volume percentage changes with temperature because volume of solution (liquid) varies with changes in temperature.
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