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प्रश्न
Derive the relation between freezing point depression and molar mass of solute.
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उत्तर
We know ΔTf ∝ m or ΔTf = Kf m
∴ `m = (ΔT_f)/K_f` ... (i)
Also, Molality, m = `(1000 xx W_2)/(M_2 xx W_1)` ... (ii)
Comparing both the equations,
`(ΔT_f)/K_f`
= `(1000 xx W_2)/(M_2 xx W_1)`
∴ `M_2 = (K_f xx 1000 xx W_2)/(ΔT_f xx W_1)`
This is the required equation.
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