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Question
Derive an expression to calculate molar mass of non-volatile solute by osmotic pressure measurement.
Solution
For very dilute solution
Where π = `(n_2RT)/V`
π = Osmotic Pressure
n2 = Number of moles of solute
R = Gas constant
T = Absolute temperature
V = Volume of solution
n2 = `(W_2 ("Mass of solute"))/(M_2 ("Molar mass of solution"))`
M2 = `(W_2RT)/(πV)`
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