Why is it desirable to express concentration as molality rather than molarity?

Question

Why is it desirable to express concentration as molality rather than molarity when performing experiments in which the temperature changes?

Answer 1

Molality is often used when dissolving in slovents other than water. A clear example would be when making an alloy of two metals mixed together, such as brass, bronze, etc. It is not meaningful to talk of a mixed solution, which is implied with molarity.

Molality is also used for "colligative" properties, such as freezing point depression and boiling point elevation. These properties are based on moles dissolved in kg. of solvent, rather than liters of solution.

Answer 2

Unit For Molality

Answer 3

i might want to imagine that's a count number number of ease, not necessity. The molality (which measures the load of the solute) may be better relatable to someone than molarity (which measures the moles). those who are not acquainted with the mole or with the conversion between weight and moles might want to be better smooth with molality than morality. obviously, it truly is basically my opinion, i don't believe of it is "mandatory" to exhibit one over the different.

Answer 4

because the mass of a substance never changes, wheras the volume is dependant on temperature.
molality is concentration by mass and molarity is concentration by volume.