Two solutions of non-volatile solutes $A$ and $B$ having molar mass ratio of $A$ and $B$ $(M_{A} / M_{B})$ as $1 / 3$ are prepared by dissolving $5$ % (mass/vol.) of each in water.
Calculate the ratio of freezing point depression.

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Solution

$(M_{A} / M_{B}) = 1 / 3$
Also $Δ T_{f} = K_{b} \times m$
Hence, $Δ T_{A} / Δ T_{B} = m_{A} / m_{B} = M_{B} / M_{A} = 3 / 1$

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Two solutions of non-volatile solutes A and B having molar mass ratio of A and B (MA/MB) as 1/3 are prepared by dissolving 5% (mass/vol.) of each in water. Calculate the ratio of freezing point depression.

(MA/MB)=1/3Also ΔTf=Kb×mHence, ΔTA/ΔTB=mA/mB=MB/MA=3/1

Two solutions of non-volatile solutes $A$ and $B$ having molar mass ratio of $A$ and $B$ $(M_{A} / M_{B})$ as $1 / 3$ are prepared by dissolving $5$ % (mass/vol.) of each in water.
Calculate the ratio of freezing point depression.

$(M_{A} / M_{B}) = 1 / 3$
Also $Δ T_{f} = K_{b} \times m$
Hence, $Δ T_{A} / Δ T_{B} = m_{A} / m_{B} = M_{B} / M_{A} = 3 / 1$