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Page No 187: - Chapter 7 - P - Block Elements - Intext Solutions - Ncert Solutions class 12 - Chemistry

Updated On 11-02-2025 By Lithanya


Question 7.18:

Why does O3 act as a powerful oxidising agent?

Answer:

Ozone is not a very stable compound under normal conditions and decomposes readily on heating to give a molecule of oxygen and nascent oxygen. Nascent oxygen, being a free radical, is very reactive.

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Therefore, ozone acts as a powerful oxidising agent.

Question 7.19:

How is O3 estimated quantitatively?

Answer:

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.

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