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Vapour pressure of pure water at 298 K i | Class 12 Chemistry Chapter Solutions, Solutions NCERT Solutions

Question:

Vapour pressure of pure water at 298 K is 23.8 mm Hg. 50 g of urea (NH₂CONH₂) is dissolved in 850 g of water. Calculate the vapour pressure of water for this solution and its relative lowering.

Answer:

It is given that vapour pressure of water,P_I^o = 23.8 mm of Hg

Weight of water taken, w₁= 850 g

Weight of urea taken, w₂= 50 g

Molecular weight of water, M₁= 18 g mol^{- 1}

Molecular weight of urea, M₂= 60 g mol^{- 1}

Now, we have to calculate vapour pressure of water in the solution. We take vapour pressure as p₁.

Now, from Raoult's law, we have:

Hence, the vapour pressure of water in the given solution is 23.4 mm of Hg and its relative lowering is 0.0173.

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Comments

Dhruv Kaushik
2019-12-18 22:34:32

Or practise isi type k numerical ki batana Nice method well

Syed Abdullah
2019-08-08 20:50:09

Answer is 23.1

Syed Abdullah
2019-08-08 20:48:11

Thanks uhhh

Annaya Sharma
2019-07-26 23:32:26

Ye answer book me nhi hai

Aqeel Ahmad
2019-05-28 14:24:19

Relative lowering kaise aaya

Shivam
2019-05-23 22:23:28

This is not the answer of my questions plz coelrrect it

Preeti
2019-05-21 19:09:15

Rlvp=pÂ°1-p1/pÂ°1= 23.8 -23.4/23.8= 0.4/23.8=0.0168 Rlvp =0.017(approx)

Doubter
2019-04-25 10:18:27

But the answer is 289.5 bar. Which is nentioned in 12th NCEET book.

Ankita
2019-04-12 05:16:38

Relative lowering kaise nikala vo bhi toh btao

AMEENA
2019-04-04 21:14:08

vapour pressure in mm hg of 0.1 mole of urea in 180 g of water at 25 C is(the vapour pressure of water at 25 C is 24 mm hg)

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Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 9: Vapour pressure of pure water at 298 K is 23.8 mm Hg. 50 g of urea (NH2CONH2) is dissolved in 850 g ....

Vapour pressure of pure water at 298 K i | Class 12 Chemistry Chapter Solutions, Solutions NCERT Solutions

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