The air is a mixture of a number of gase | Class 12 Chemistry Chapter Solutions, Solutions NCERT Solutions

Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter Solutions. This page offers a step-by-step solution to the specific question from Exercise 2, Question 39: . With detailed answers and explanations for each chapter, students can strengthen their understanding and prepare confidently for exams. Ideal for CBSE and other board students, this resource will simplify your study experience.

Question 39:

The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approximate proportion of 20% is to 79% by volume at 298 K. The water is in equilibrium with air at a pressure of 10 atm. At 298 Kif the Henry's law constants for oxygen and nitrogen are 3.30 x 107 mm and 6.51 x 107mm respectively, calculate the composition of these gases in water.

Answer:

Percentage of oxygen (O2) in air = 20 %

Percentage of nitrogen (N2) in air = 79%

Also, it is given that water is in equilibrium with air at a total pressure of 10 atm, that is, (10 × 760) mm Hg = 7600 mm Hg

Therefore, Partial pressure of oxygen, po2 = 20/100 *7600

=1520 mm Hg

Partial pressure of nitrogen,pN2 = 79/100 *7600

= 6004 mmHg

Now, according to Henry's law:

p = KH.x

For oxygen:

po2  = KH. xO2

xO2 po2 / KH

= 1520 / 3.30 X 107

= 4.61 10-5

For nitrogen:

pN2 = KH.xN2

xN2 pN2 / KH

= 6004 / 6.51 x 107

= 9.22 x 10-5

Hence, the mole fractions of oxygen and nitrogen in water are 4.61 ×10 - 5 and 9.22 × 10 - 5 respectively.


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Comments

  • Bhumika Rajawat
  • Aug 11, 2019

Y r v not considering volume, when they have given proportions by volume??


  • Jaydeep kalita
  • Apr 18, 2019

The subscript 2 must be written nicely to make it more convineint.


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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 2 , Question 39: The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approxi....