Problem 168 - A Complete Resource Book in Chemistry for JEE Main

Question

Which reagents give oxygen as one of the product during oxidation with ozone? (a) \(\mathrm{H}_{2} \mathrm{~S}\) (b) \(\mathrm{PbS}\) (c) \(\mathrm{SO}_{2}\) (d) \(\mathrm{SnCl}_{2} / \mathrm{HCl}\)

Step-by-Step Solution

Answer

The reagent \(\mathrm{SO}_2\) releases oxygen when oxidized with ozone.

Step 1: Understanding Ozone Oxidation

Ozone (\(O_3\)) is a strong oxidizing agent that can react with various substances to produce oxygen gas as one of the products. The key to solving this problem is understanding which substances, when oxidized by ozone, result in the formation of \(O_2\).

Step 2: Identifying Oxidation Reactions

Review each reagent to determine if their reaction with ozone could produce oxygen:- \(\mathrm{H}_2\mathrm{S}\) and \(\mathrm{PbS}\) can undergo oxidation where sulfur compounds get oxidized, but typically not yielding only oxygen.- \(\mathrm{SO}_2\), when oxidized by ozone, forms \(\mathrm{SO}_3\) and releases oxygen gas as one of the by-products.- \(\mathrm{SnCl}_2/\mathrm{HCl}\) does not release \(\mathrm{O}_2\) when oxidized by ozone.

Step 3: Determining the Correct Option

Since \(\mathrm{SO}_2\) reacts with ozone to form \(\mathrm{SO}_3\) and releases \(\mathrm{O}_2\), it is the reagent that results in oxygen production in this context. No such generation of oxygen occurs with the other reagents listed.

Key Concepts

Ozone as oxidizing agent

Ozone, represented chemically as \(O_3\), is a potent oxidizing agent. It is well known for its ability to react with various chemicals, altering their oxidation state. Oxidizing agents are substances that can accept electrons and hence, are involved in electron transfer reactions. Ozone’s oxidation power comes from its tendency to get reduced by accepting electrons and in the process, breaking apart and forming other products.

• It can react with metals, non-metals, and even complex molecules through these oxidation reactions.
• Ozone tends to produce oxygen gas as a by-product in many of these reactions.

Its strong oxidative capabilities make it useful in applications such as cleaning, purification, and even in some environmental remediation processes. Ozone effectively alters the composition of reacting substances, often resulting in the production of simpler, more stable products.

Oxygen production in reactions

Oxygen gas, \(O_2\), is a common product in many oxidation reactions involving ozone. When ozone reacts with substances capable of donating electrons, this leads to the breakdown of ozone itself. Through this process, the formation of oxygen takes place.

• For example, when ozone reacts with sulfur dioxide \(SO_2\), the reaction forms sulfur trioxide \(SO_3\) and releases oxygen gas as a by-product.
• This transformation is significant as it showcases ozone's ability to bond conversions that release molecular oxygen.

Understanding the conditions under which oxygen is released is important for utilizing ozone in chemical reactions where oxygen production is desired. This characteristic aligns with industrial and environmental applications, where efficient oxygen generation is beneficial.

Oxidation reactions with ozone

In oxidation reactions with ozone, the nature of the reactant determines the products formed. The reactions encompass the principle of gaining oxygen or losing hydrogen, accompanying electron transfer. In the context of the initial exercise: when ozone is used as the oxidizing agent, different results occur based on the reactant involved.

• With \(SO_2\), it efficiently oxidizes to form \(SO_3\) and simultaneously oxygen gas \(O_2\), demonstrating a classic oxidation reaction.
• Other compounds like \(H_2S\) and \(PbS\) can undergo oxidation, but not always in a way that results in just oxygen production.

The ability of ozone to selectively oxidize compounds speaks to the specificity of some chemical reactions. This specificity can be harnessed in targeted chemical syntheses and in processes where selective reaction pathways are essential. Understanding these reactions enhances our ability to predict and manipulate chemical processes efficiently.