Home
Class 12
CHEMISTRY
By dissolving 13.6 g of a substance in 2...

By dissolving `13.6 g` of a substance in `20 g` of water, the freezing point decreased by `3.7^(@)C`. Calculate the molecular mass of the substance. (Molal depression constant for water `= 1.863K kg mol^(-1))`

Text Solution

Verified by Experts

`Mw_(2)=(1000 K _(f)W_(2))/(W_(1)xxDeltaT)`
Given,`K_(f)=1.863 K kg mol^(-1)`
`W_(2)=13.6 g`,`W_(1)=20 g , DeltaT=3.7^(@)C`
`(Mw_(2)) = (1000xx1.863xx13.6)/(20xx3.7) =342.39`
Promotional Banner

Similar Questions

Explore conceptually related problems

A solution containg 12 g of a non-electrolyte substance in 52 g of water gave boiling point elevation of 0.40 K . Calculate the molar mass of the substance. (K_(b) for water = 0.52 K kg mol^(-1))

On dissolving 0.25 g of a non-volatile substance in 30 mL benzene (density 0.8 g mL^(-1)) , its freezing point decreases by 0.25^(@)C . Calculate the molecular mass of non-volatile substance (K_(f) = 5.1 K kg mol^(-1)) .

15 g of an unknown molecular substance was dissolved in 450 g of water. The resulting solution freezes at - 0.34^(@) C. what is molar mass of the substance ? (K_(f)" for water " = 1.86 k kg " mol"^(-1))

1.355 g of a substance dissolved in 55 g of CH_(3)COOH produced a depression in the freezing point of 0.618^(@)C . Calculate the molecular weight of the substance (K_(f)=3.85)

The freezing point of 1 molal NaCl solution assuming NaCl to be 100% dissociated in water is (Molal depression constant of water=1.86Kkg/mol)

1.0 g of non - electrolyte solute dissolved in 50 g of benzene lowered the freezing point of benzene by 0.4 K. Find the molar mass of the solute. [Given : Freezing point depression constant of benzene = 5.12 K. kg mol].

10g of an organic substance when dissolved in two litres of water gave an osmotic pressure of 0.59 atm, at 7^(@)C . Calculate the molecular weight of the substance.