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Ch.22 - Chemistry of the Nonmetals
Chapter 22, Problem 79

Complete the exercises below. Indicate whether each of the following statements is true or false. 2SO₂ (g) + O₂ (g) → 2SO₃ (g) is an example of a disproportionation reaction.

Verified step by step guidance
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Step 1: Understand the concept of a disproportionation reaction. A disproportionation reaction is a type of redox reaction in which a single substance is simultaneously oxidized and reduced, forming two different products.
Step 2: Analyze the given chemical equation: 2SO₂ (g) + O₂ (g) → 2SO₃ (g). Identify the reactants and products in the reaction.
Step 3: Determine the oxidation states of sulfur in the reactants and products. In SO₂, sulfur has an oxidation state of +4, and in SO₃, sulfur has an oxidation state of +6.
Step 4: Check if the same element is both oxidized and reduced. In this reaction, sulfur in SO₂ is only oxidized to form SO₃, and there is no reduction of sulfur occurring.
Step 5: Conclude whether the reaction is a disproportionation reaction. Since sulfur is only oxidized and not reduced, this reaction is not a disproportionation reaction.

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Disproportionation Reaction

A disproportionation reaction is a specific type of redox reaction in which a single substance is both oxidized and reduced, resulting in two different products. In these reactions, one element undergoes an increase in oxidation state while another undergoes a decrease. This process is crucial for understanding how certain elements can react in multiple ways, often leading to the formation of different compounds.
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Oxidation States

Oxidation states (or oxidation numbers) are a way to keep track of electrons in chemical reactions, particularly in redox processes. They indicate the degree of oxidation of an atom in a compound, helping to identify which atoms are oxidized and which are reduced. Understanding oxidation states is essential for determining whether a reaction is a disproportionation reaction or not.
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Balancing Chemical Reactions

Balancing chemical reactions involves ensuring that the number of atoms of each element is the same on both sides of the equation. This is important for obeying the law of conservation of mass. In the context of the given reaction, balancing helps to analyze the changes in oxidation states and determine the nature of the reaction, including whether it qualifies as disproportionation.
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