Get Answers to all your Questions

header-bg qa

(a) 30 g of urea (M = 60 g mol-1) is dissolved in 846 g of water. Calculate the vapour pressure of water for this solution if vapour pressure of pure water at 298 K is 23·8 mm Hg.
(b) Write two differences between ideal solutions and non-ideal solutions.

 

 

 

 
 
 
 
 

Answers (1)

best_answer

(a) Wurea = 30 g (WB) B = urea
     Murae = 60 g/mol
    Nurea = \frac{W}{M}= \frac{30}{60}= 0\cdot 5
  Wwater = 846 g (WA) A = water
  Mwater = 18 g/mol
  nwater = 47
 \frac{p^{0}_{A}-ps}{p^{0}_{A}}= \frac{n_{B}}{n_{A}+n_{B}}
\frac{23\cdot 8-ps}{23\cdot 8}= \frac{0\cdot 5}{47+0\cdot 5}
ps = 23.55 mm hg


(b)

Ideal solution Non-Ideal solution
(1) Each component of a ideal solution obey Raoult's
law in solution
component of non-ideal solution
dose not obey Rabcilt's law.
(2)\Delta H_{mix}= 0, i.e no heat is evolved or absorbed
during formation of solution
\Delta H_{mix}\neq 0, i.e heat is either evolved or absorbed during the formation of solution

 

Posted by

Sumit Saini

View full answer

Crack CUET with india's "Best Teachers"

  • HD Video Lectures
  • Unlimited Mock Tests
  • Faculty Support
cuet_ads