A student forgot to add the reaction mix | Class 11 Chemistry Chapter States of Matter, States of Matter NCERT Solutions

Welcome to the NCERT Solutions for Class 11 Chemistry - Chapter States of Matter. This page offers a step-by-step solution to the specific question from Exercise 1, Question 11: . 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 11:

A student forgot to add the reaction mixture to the round bottomed flask at 27 °C but instead he/she placed the flask on the flame. After a lapse of time, he realized his mistake, and using a pyrometer he found the temperature of the flask was 477 °C. What fraction of air would have been expelled out?

Answer:

Let the volume of  air in the  flask at 27°C be V1 & that of the same amount of the gas at 477°C be V2.

According to charle’s law

V2/T2  =  V1/ T1   …………………(1)

NOW  volume of gas expelled out = V2 – V1, THEN

Fraction of the gas expelled out = (V2 – V1 ) / V2 = 1- (V1/ V2)     …………….(2)

Also from equation (1)  V1/ V2 = T1/ T2   …………..(3)

Substituting the values of (3) in (2), we get

Fraction of the air expelled  = 1- T1/ T2 = (T2 – T1)/ T2

 = 750- 300 /750 = 0.6

Hence, fraction of air expelled out is 0.6 or 3/5 th


Study Tips for Answering NCERT Questions:

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:

  • Read the question carefully and focus on the core concept being asked.
  • Reference examples and data from the chapter when answering questions about States of Matter.
  • 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.
  • Discuss your answers with your teachers or peers to get feedback and improve your understanding.

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Comments

  • Oj
  • Aug 30, 2018

Why did you do V2 - V1 and not V1-V2 as v1 has more volume than v2???


  • Riya Pandey
  • Aug 28, 2018

Thank you


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Welcome to the NCERT Solutions for Class 11 Chemistry - Chapter . This page offers a step-by-step solution to the specific question from Excercise 1 , Question 11: A student forgot to add the reaction mixture to the round bottomed flask at 27 °C but instead he....