Why molality is preferred over molarity ...

Why molality is preferred over molarity in expressing the concentration of solution ?

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Molality is the number of moles of the solute present in 1 kg of the solvent whereas molarity is the number of moles of the solute present per litre of the solution. Thus, molality involves only masses which do not change with temperature whereas molarity involves volume which change with temperature. Hence, molality is preferred over molarity.

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Assertion : Molality is perferred to molarity for expression the concentration of the solution. Reason : Molality can be determined more easily than molarity.

If both assertion are reason are correct and reason is correct explanation for assertion.

If both assertion and reason are corrct but reason is not correct explanation for assertion.

If assertion is corrct but reason is incorrect.

If assertion and reason both are incrrect.

Method of expressing concentration of solution is

mass percentage.

volume percentage.

mass by volume percentage.

all the above.

Molar concentration ( M ) of any solution =

`("No. of moles of solute")/( "Volume of solution in litre")`

`("No. of gram equivalent of solute")/("Volume of solution in litre")`

`("No. of moles of solute")/("Mass of solvent in Kg")`

`("No. of moles of any constituent")/("Total no. of moles of all constituents")`