Determine the amount of CaCl2 (i = 2.47) | Class 12 Chemistry Chapter Solutions, Solutions NCERT Solutions

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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 40:

Determine the amount of CaCl2 (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27°C.

. 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 40:

Determine the amount of CaCl2 (i = 2.47) dissolved in 2.5 litre of water such that its osmotic pressure is 0.75 atm at 27°C.

Answer:

We know that

π = i n/V RT

⇒π = i w/MV iRT

⇒ w = πMV /  iRT     .......................(1)

Now we have given below values:

π =  0.75 atm

V = 2.5L

i = 2.47

T = (27+273) K = 300K

Here,

R = 0.0821L atm k-1 mol-1

M = 1x40 + 2x35.5

= 111 g/mol

Now putting the value in equation 1:

w =  0.75x111x2.5 / 2.47x0.0821x300

=3.42g

Hence, the required amount of CaCl2 is 3.42 g.


Study Tips for Answering NCERT Questions:

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  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about Solutions.
  • Review previous year question papers to get an idea of how such questions may be framed in exams.
  • Practice answering questions within the time limit to improve your speed and accuracy.
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Comments

  • Mohit
  • Dec 10, 2019

It is really helpful.....


  • Adi
  • Jun 19, 2019

nice site


  • Soju
  • May 24, 2019

Put the value of R=8.314 instead of putting 0.0821 ,then will get the right answer that is 0.03mol.


  • Aryan raaz
  • Apr 16, 2019

But sir NCERT me to answer 0.03 mol de rha hai Is answer se to 0.003 mol aa rha hai Kya karu


  • Kaushik
  • Apr 08, 2019

Good site.Has each answer.


  • Sourabh
  • Feb 26, 2019

I help this answer


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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 40: Determine the amount of CaCl2 (i = 2.47) dissolved in 2.5 litre of water such that its osmotic press....

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