Question

how does molarity and molality vary in temp

Answer 1

Dear Student

Molarity (M) = moles of solute per litre solution
So, with temperature, it will vary since volume of solute will change with temperature, but solubility may increase or decrease. A definite formula can not be given for change in molarity with change in temperature, but it will change.

Molality (m) = moles of solute per kilogram of solvent.
Commonly, it is thought that molality will not change with temperature as mass (Kg) of solvent does not change, but solubility can change with temperature, so it will change.

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