This chapter belongs to a previous NCERT/CBSE curriculum and is not part of the current 2026-27 chapter list. Removed in 2022-23.
Welcome to the NCERT Solutions for Class 12 Chemistry - Chapter The p-Block Elements. This page offers a step-by-step solution to the specific question from Exercise 1, Question 19:
How is O3 estimated quantitatively?
. 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.How is O3 estimated quantitatively?
Quantitatively, ozone can be estimated with the help of potassium iodide. When ozone is made to react with potassium iodide solution buffered with a borate buffer (pH 9.2), iodine is liberated. This liberated iodine can be titrated against a standard solution of sodium thiosulphate using starch as an indicator. The reactions involved in the process are given below.
2I- + H2O + O3 → 2OH- + I2 + O2
Iodide Ozone Iodine
I2 + 2Na2S2O3 → Na2S4O6 + NaI
Sodium Sodium
thiosulphate tetrathionate
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 1 , Question 19: How is O3 estimated quantitatively?....
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Comments
Do you have your own app for all subjects?
weight of sodium iodide obtained is equal to weight reacted
Its nice but how the quantity estimate by this??
Nice
Oh yes this is the mistake that I have doneðŸË¶ðŸË¶
I got, thanks
bhai kuch na smjh aaya
Nice
Nice. I understand clearly
GREAT IT'S HELP FULL..... BUT HOW THE QUANTITY ESTIMATE BY THIS?