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The freezing point of solution is –1° C, when 6 gram urea is dissolved in 100 gram water. If 342 gram sugar is dissolved in 1000 gram water, then the freezing point of the solution will be... .

kinu rk , 15 Years ago
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SAGAR SINGH - IIT DELHI

Dear student,

Freezing point depression is given by Ebbing. The freezing point depression ΔTf is a colligative property of the solution, and for dilute solutions is found to be proportional to the molal concentration cm of the solution:

ΔTf = Kfcm

Where Kf is called the freezing-point-depression constant.

Last Activity: 15 Years ago
vikas askiitian expert

depression in frezing point = kb m

6gm urea when dissolved in 100gm water , molality (m)= moles of solute/mass of solvent in kg

molar mass of urea = 60

      m = (6/60)/(0.1) = 1

depression in freezing point = (0-1) = 1= dT

now using fomula , dT = kbm

     Kb = 1         .....................1

 

now for another solution using same formula ,

 molality of solution , moles/mass of solvent in kg = (342/342)/1 = 1

m = 1

molar mass of sugar = 342

now by using same formula , dT = kbm = 1                    (use Kb from eq 1)

it means that frezing point of water is againg -1oC...

 

approve if u like my ans

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Last Activity: 15 Years ago
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