Problem 26 - Chemistry in 30 days

Question

Chlorine on reaction with excess of ammonia produces (a) \(\mathrm{NCl}_{3}\) and \(\mathrm{HCl}\) (b) \(\mathrm{N}_{2}\) and \(\mathrm{HCl}\) (c) \(\mathrm{NH}_{2} \mathrm{Cl}\) and \(\mathrm{NH}_{4} \mathrm{Cl}\) (d) \(\mathrm{N}_{2}\) and \(\mathrm{NH}_{4} \mathrm{Cl}\)

Step-by-Step Solution

Answer

The correct answer is (d) \(\text{N}_2\) and \(\text{NH}_4\text{Cl}\).

Step 1: Understanding the Reaction

When chlorine reacts with ammonia, different nitrogen-chlorine products can be formed depending on the conditions. In this case, we are interested in knowing what happens when chlorine is in excess and reacts with ammonia.

Step 2: Reaction Analysis

The reaction between chlorine and ammonia when ammonia is in excess is as follows: \[ 8 ext{NH}_3 + 3 ext{Cl}_2 ightarrow 6 ext{NH}_4 ext{Cl} + ext{N}_2 \] This reaction forms nitrogen gas \(\text{N}_2\) and ammonium chloride \(\text{NH}_4 ext{Cl}\) as products.

Step 3: Identifying the Products

According to the balanced chemical equation, the products of the reaction when ammonia is in excess are nitrogen gas \(\text{N}_2\) and ammonium chloride \(\text{NH}_4 ext{Cl}\).

Step 4: Selecting the Correct Option

From the given choices, the products \(\text{N}_2\) and \(\text{NH}_4 ext{Cl}\) correspond to the choice (d).

Key Concepts

Nitrogen-Chlorine Products

When chlorine reacts with ammonia, the products formed can vary, dependent on whether there is an excess of chlorine or ammonia. If ammonia is in excess, the reaction primarily forms nitrogen gas (\(\mathrm{N}_2\)) and ammonium chloride (\(\mathrm{NH}_4\mathrm{Cl}\)). These are the nitrogen-chlorine products we're interested in when considering such a reaction condition.
Given the possibility of different reactions:

• If chlorine is in excess, then trichloramine (\(\mathrm{NCl}_3\)) could be a product.
• If the conditions favor the formation of chloramines, monochloramine (\(\mathrm{NH}_2\mathrm{Cl}\)) might form.

Understanding these products is crucial for predicting the outcome of reactions involving nitrogen and chlorine, especially in industrial and environmental contexts.

Ammonium Chloride Formation

Ammonium chloride (\(\mathrm{NH}_4\mathrm{Cl}\)) is an essential product formed when chlorine and an excess of ammonia react. This process results in the liberation of nitrogen gas and solid ammonium chloride.
To understand how ammonium chloride forms, consider the basic chemical reaction:

• The ammonia (\(\mathrm{NH}_3\)) acts as a base, accepting a proton from hydrochloric acid (\(\mathrm{HCl}\)), which forms in situ during the reaction of ammonia and chlorine.
• Simultaneously, \(\mathrm{NH}_3\) reacts with \(\mathrm{HCl}\) forming \(\mathrm{NH}_4\mathrm{Cl}\).

This substance is typically a white crystalline salt and has numerous uses, including in fertilizers and used as a flavoring agent in some food products.

Chemical Reaction Analysis

Analyzing the chemical reaction between chlorine and ammonia involves understanding the stoichiometry and conditions that determine the products. In the given scenario, where ammonia is the excess reactant, the balanced reaction is:\[ 8 \, \mathrm{NH}_3 + 3 \, \mathrm{Cl}_2 \rightarrow 6 \, \mathrm{NH}_4\mathrm{Cl} + \, \mathrm{N}_2 \]
**Key steps in this analysis include:**

• Reactant Balance: The equation shows that eight molecules of ammonia react with three molecules of chlorine.
• Product Formation: The primary products are nitrogen gas and ammonium chloride. Six ammonium chloride and one nitrogen molecule are formed.
• Optimized Conditions: This particular product distribution occurs because of the controlled amount of chlorine, ensuring that all ammonia reacts to form ammonium chloride.

Understanding these aspects helps in optimizing such reactions for industrial processes to ensure the desired product output is achieved consistently.