Of The Reactions Below, Which One Is A Double-replacement Reaction?A. $NH_4Cl \rightarrow NH_3 + HCl$B. $2Mg + O_2 \rightarrow 2MgO$C. $Cd(NO_3)_2 + Na_2S \rightarrow CdS + 2NaNO_3$D. $2N_2 + 3H_2 \rightarrow 2NH_3$

Double-replacement reactions are a type of chemical reaction where two compounds exchange partners, resulting in the formation of two new compounds. This type of reaction is also known as a double-displacement reaction. In this article, we will explore the concept of double-replacement reactions and identify which of the given reactions is a double-replacement reaction.

What is a Double-Replacement Reaction?

A double-replacement reaction involves the exchange of partners between two compounds. This type of reaction typically involves two compounds that are dissolved in a solvent, such as water. The reaction occurs when the ions of the two compounds exchange partners, resulting in the formation of two new compounds.

Characteristics of Double-Replacement Reactions

Double-replacement reactions have several characteristics that distinguish them from other types of chemical reactions. Some of the key characteristics of double-replacement reactions include:

• Exchange of partners: The ions of the two compounds exchange partners, resulting in the formation of two new compounds.
• Formation of new compounds: The reaction results in the formation of two new compounds, which are different from the original compounds.
• No change in oxidation state: The oxidation state of the ions remains the same during the reaction.

Examples of Double-Replacement Reactions

Some common examples of double-replacement reactions include:

• Sodium chloride and silver nitrate: When sodium chloride (NaCl) is mixed with silver nitrate (AgNO3), a double-replacement reaction occurs, resulting in the formation of silver chloride (AgCl) and sodium nitrate (NaNO3).
• Calcium carbonate and hydrochloric acid: When calcium carbonate (CaCO3) is mixed with hydrochloric acid (HCl), a double-replacement reaction occurs, resulting in the formation of calcium chloride (CaCl2) and carbon dioxide (CO2).

Analyzing the Given Reactions

Now that we have a good understanding of double-replacement reactions, let's analyze the given reactions to determine which one is a double-replacement reaction.

Reaction A: $NH_4Cl \rightarrow NH_3 + HCl$

This reaction involves the decomposition of ammonium chloride (NH4Cl) into ammonia (NH3) and hydrogen chloride (HCl). This reaction is not a double-replacement reaction because it involves the decomposition of a single compound into two products.

Reaction B: $2Mg + O_2 \rightarrow 2MgO$

This reaction involves the reaction of magnesium (Mg) with oxygen (O2) to form magnesium oxide (MgO). This reaction is not a double-replacement reaction because it involves the combination of two elements to form a single compound.

Reaction C: $Cd(NO_3)_2 + Na_2S \rightarrow CdS + 2NaNO_3$

This reaction involves the reaction of cadmium nitrate (Cd(NO3)2) with sodium sulfide (Na2S) to form cadmium sulfide (CdS) and sodium nitrate (NaNO3). This reaction is a double-replacement reaction because it involves the exchange of partners between two compounds, resulting in the formation of two new compounds.

Reaction D: $2N_2 + 3H_2 \rightarrow 2NH_3$

This reaction involves the reaction of nitrogen (N2) with hydrogen (H2) to form ammonia (NH3). This reaction is not a double-replacement reaction because it involves the combination of two elements to form a single compound.

Conclusion

In conclusion, the reaction that is a double-replacement reaction is:

• Reaction C: $Cd(NO_3)_2 + Na_2S \rightarrow CdS + 2NaNO_3$

This reaction involves the exchange of partners between two compounds, resulting in the formation of two new compounds. This reaction is a classic example of a double-replacement reaction.

Key Takeaways

• Double-replacement reactions involve the exchange of partners between two compounds, resulting in the formation of two new compounds.
• Double-replacement reactions have several characteristics, including the exchange of partners, formation of new compounds, and no change in oxidation state.
• Examples of double-replacement reactions include the reaction of sodium chloride and silver nitrate, and the reaction of calcium carbonate and hydrochloric acid.
• The reaction that is a double-replacement reaction is Reaction C: $Cd(NO_3)_2 + Na_2S \rightarrow CdS + 2NaNO_3$.
  Double-Replacement Reactions: A Q&A Guide =============================================

Double-replacement reactions are a fundamental concept in chemistry, and understanding them is crucial for success in chemistry classes and beyond. In this article, we will answer some of the most frequently asked questions about double-replacement reactions.

Q: What is a double-replacement reaction?

A: A double-replacement reaction is a type of chemical reaction where two compounds exchange partners, resulting in the formation of two new compounds. This type of reaction is also known as a double-displacement reaction.

Q: What are the characteristics of double-replacement reactions?

A: Double-replacement reactions have several characteristics, including:

• Exchange of partners: The ions of the two compounds exchange partners, resulting in the formation of two new compounds.
• Formation of new compounds: The reaction results in the formation of two new compounds, which are different from the original compounds.
• No change in oxidation state: The oxidation state of the ions remains the same during the reaction.

Q: What are some examples of double-replacement reactions?

A: Some common examples of double-replacement reactions include:

• Sodium chloride and silver nitrate: When sodium chloride (NaCl) is mixed with silver nitrate (AgNO3), a double-replacement reaction occurs, resulting in the formation of silver chloride (AgCl) and sodium nitrate (NaNO3).
• Calcium carbonate and hydrochloric acid: When calcium carbonate (CaCO3) is mixed with hydrochloric acid (HCl), a double-replacement reaction occurs, resulting in the formation of calcium chloride (CaCl2) and carbon dioxide (CO2).

Q: How do I identify a double-replacement reaction?

A: To identify a double-replacement reaction, look for the following:

• Two compounds: The reaction involves two compounds that are exchanging partners.
• Exchange of partners: The ions of the two compounds exchange partners, resulting in the formation of two new compounds.
• Formation of new compounds: The reaction results in the formation of two new compounds, which are different from the original compounds.

Q: What are some common mistakes to avoid when working with double-replacement reactions?

A: Some common mistakes to avoid when working with double-replacement reactions include:

• Not identifying the exchange of partners: Failing to recognize the exchange of partners between the two compounds can lead to incorrect identification of the reaction.
• Not considering the formation of new compounds: Failing to consider the formation of new compounds can lead to incorrect identification of the reaction.
• Not accounting for the no change in oxidation state: Failing to account for the no change in oxidation state can lead to incorrect identification of the reaction.

Q: What are some real-world applications of double-replacement reactions?

A: Double-replacement reactions have several real-world applications, including:

• Water treatment: Double-replacement reactions are used in water treatment to remove impurities and contaminants from water.
• Pharmaceuticals: Double-replacement reactions are used in the production of pharmaceuticals to create new compounds with specific properties.
• Materials science: Double-replacement reactions are used in materials science to create new materials with specific properties.

Q: How can I practice working with double-replacement reactions?

A: To practice working with double-replacement reactions, try the following:

• Work through examples: Work through examples of double-replacement reactions to practice identifying the exchange of partners, formation of new compounds, and no change in oxidation state.
• Solve problems: Solve problems that involve double-replacement reactions to practice applying the concepts to real-world scenarios.
• Experiment with reactions: Experiment with reactions to see how they occur and to practice identifying the exchange of partners, formation of new compounds, and no change in oxidation state.

Conclusion

In conclusion, double-replacement reactions are a fundamental concept in chemistry, and understanding them is crucial for success in chemistry classes and beyond. By practicing identifying double-replacement reactions, working through examples, solving problems, and experimenting with reactions, you can become proficient in working with double-replacement reactions.