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 38: . 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.
Benzene and toluene form ideal solution over the entire range of composition. The vapour pressure of pure benzene and toluene at 300 K are 50.71 mm Hg and 32.06 mm Hg respectively. Calculate the mole fraction of benzene in vapour phase if 80 g of benzene is mixed with 100 g of toluene.
Molar mass of benzene(C6H6) = 6 X 12 + 6 X 1 = 78 g/mol
Molar mass of toluene = 7 x 12 + 8 x 1 = 92 g/mol
Now no of moles in 80g of benezen = 80 / 78 = 1.026 mol
No of moles in 100g of toluene = 100 / 92 = 1.087 mol
∴Mole fraction of benzene xb = 1.026 / 1.026 + 1.087 = 0.486
And Mole fraction of toluene,xt = 1 - 0.486 = 0.514
We have given that
Vapor pressure of pure benzene pb° = 50.71 mm Hg
And, vapour pressure of pure toluene, pt° = 32.06 mm Hg
Therefore partial Vapor pressure of benzene, pb = pb X xb
= 50.71 x 0.486
= 24.65 mm Hg
And partial Vapor pressure of toluene, pt = pt X xt
Pt = p°t X xt = 32.06 x 0.514
= 16.48
Total vapour pressure = 24.65 + 16.48 = 41.13 mm Hg
Mole fraction of benzene in vapour phase = 24.65 / 41.13 = 0.60
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 |
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Read MoreWelcome 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 38: Benzene and toluene form ideal solution over the entire range of composition. The vapour pressure of....
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It's do long and difficult so tell any other way to solve it
Any more Satisfactory way to solve