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Academic session 2026-27, Chapter 1 in the current curriculum.
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:
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.
. 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.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.
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.
The reaction between A and B is first order with respect to A and zero order with respect to B. Fill in the blanks in the following table:
| Experiment |
A/ mol L - 1 |
B/ mol L - 1 |
Initial rate/mol L - 1 min - 1 |
| I | 0.1 | 0.1 |
2.0 × 10 - 2 |
| II | -- | 0.2 |
4.0 × 10 - 2 |
| III | 0.4 | 0.4 | -- |
| IV | -- | 0.2 |
2.0 × 10 - 2 |
NCERT questions are designed to test your understanding of the concepts and theories discussed in the chapter. Here are some tips to help you answer NCERT questions effectively:
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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....
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Comments
Y r v not considering volume, when they have given proportions by volume??
The subscript 2 must be written nicely to make it more convineint.