Question

Which one of the following reactions does not form gaseous product? (a) \(\mathrm{PbS}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow\) (b) \(\mathrm{Cl}_{2}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow\) (c) \(\mathrm{PbO}_{2}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow\) (d) Acidified \(\mathrm{KMnO}_{4}+\mathrm{H}_{2} \mathrm{O}_{2} \rightarrow\)

Short answer

Reaction A (\(\mathrm{PbS} + \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow\)) does not form a gaseous product.

Step-by-step solution

Understand Reaction A

Evaluate the reaction \( \mathrm{PbS} + \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \). Lead(II) sulfide (\(\mathrm{PbS}\)) can react with hydrogen peroxide (\(\mathrm{H}_{2} \mathrm{O}_{2}\)) to form lead sulfate (\(\mathrm{PbSO}_{4}\)) and water (\(\mathrm{H}_{2}\mathrm{O}\)). There is no gaseous product formed.

Analyze Reaction B

For the reaction \( \mathrm{Cl}_{2} + \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \), chlorine (\(\mathrm{Cl}_{2}\)) can react with hydrogen peroxide to form hydrochloric acid (\(\mathrm{HCl}\)) and oxygen gas (\(\mathrm{O}_{2}\)). Thus, a gaseous product (oxygen) is produced.

Examine Reaction C

In the reaction \( \mathrm{PbO}_{2} + \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \), lead(IV) oxide (\(\mathrm{PbO}_{2}\)) reacts with hydrogen peroxide to produce lead(II) sulfate and water. However, no gaseous product is formed in this reaction.

Consider Reaction D

Acidified permanganate reacts with hydrogen peroxide in the reaction involving \( \mathrm{KMnO}_{4} + \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \), producing manganese sulfate (or equivalent compound), water, and oxygen gas. Thus, a gaseous product (oxygen) is formed in this reaction.

Identify the Non-Gaseous Reaction

Based on the analysis, reactions A and C do not produce a gaseous product. Choose one that is definite, which is option A that forms solid lead sulfate.

Key concepts

Lead(II) Sulfide Reaction

Lead(II) sulfide, or PbS, is a compound that can undergo specific reactions due to its chemical properties. In certain reactions, it interacts with other substances, like hydrogen peroxide. When PbS reacts with hydrogen peroxide (H_2O_2), there is a transformation into lead sulfate (PbSO_4) and water. This particular interaction is noteworthy because it does not produce a gas as a byproduct. This reaction is mainly about converting the sulfide to a sulfate form:\[ \mathrm{PbS} + \mathrm{H}_{2} \mathrm{O}_{2} \rightarrow \mathrm{PbSO}_{4} + \mathrm{H}_{2} \mathrm{O} \] The lack of gaseous output is significant when comparing reactions that result in gas emissions. Understanding this can help discern which reactions are more environmentally friendly or safer for certain applications.

Hydrogen Peroxide Reactions

Hydrogen peroxide ( H_2O_2) is a versatile chemical, known for its strong oxidizing properties. It reacts with various compounds, releasing oxygen gas in many cases. For example, in multiple reactions, hydrogen peroxide acts as an oxidizing agent. This means it can accept electrons and transform substances within chemical reactions:

• In the presence of chlorine gas ( Cl_2), hydrogen peroxide breaks down into hydrochloric acid ( HCl) and releases oxygen gas.
• With lead(IV) oxide ( PbO_2), it's interesting to note that it too disrupts the structure without emitting gas, forming lead sulfate and water instead.
• With acidified potassium permanganate ( KMnO_4), once again, hydrogen peroxide's oxidizing power causes the release of oxygen gas.

The diversity of hydrogen peroxide's reactions illustrates its importance in both industrial and laboratory settings, enabling the transformation of materials in controlled ways.

Gaseous Product Formation

The formation of a gaseous product in a chemical reaction often indicates a release of energy or a phase change of a compound. In the context of the given reactions: - Gaseous product arises from interactions where the compound structures change fundamentally, such as the release of oxygen gas from hydrogen peroxide. - Specifically, when hydrogen peroxide reacts with chlorine, the resulting release of oxygen gas exemplifies gaseous product formation. This is an essential concept, as it leads to changes in pressure and volume conditions. Understanding which reactions produce gases is crucial when predicting the outcomes of chemical reactions. Knowing whether a gas will form can inform how the conditions or equipment should be selected to safely conduct the reaction. This knowledge ensures safety and efficiency in practical applications.

Oxidation-Reduction Reactions

Oxidation-reduction reactions, or redox reactions, are fundamental chemical processes where the oxidation state of molecules changes. In these reactions, electrons are transferred between substances. Hydrogen peroxide is a key participant in redox reactions due to its ability to act as both an oxidizing and reducing agent. - This dual capability enables hydrogen peroxide to donate electrons in certain interactions or accept them in others, which drastically affects the outcome of the reaction. - For instance, when hydrogen peroxide reacts with acidified potassium permanganate ( KMnO_4), it functions as a reducing agent, resulting in oxygen gas production. On the other hand, Such reactions are prevalent in many chemical processes, including those used in cleaning, synthesis, and even biological systems.