Problem 109 - A Complete Resource Book in Chemistry for JEE Main

Question

When \(\mathrm{AgNO}_{3}\) is heated strongly the products formed are (a) \(\mathrm{NO}\) and \(\mathrm{NO}_{2}\) (b) \(\mathrm{NO}_{2}\) and \(\mathrm{O}_{2}\) (c) \(\mathrm{NO}_{2}\) and \(\mathrm{N}_{2} \mathrm{O}\) (d) \(\mathrm{NO}\) and \(\mathrm{O}_{2}\)

Step-by-Step Solution

Answer

When heated, AgNO_3 decomposes into NO_2 and O_2. Therefore, the correct option is (b) NO_2 and O_2.

Step 1: Understand the Decomposition Reaction

Silver nitrate (AgNO_3) undergoes thermal decomposition when heated strongly. The thermal decomposition of silver nitrate is an important consideration in this problem.

Step 2: Write the Thermal Decomposition Equation

The balanced chemical equation for the thermal decomposition of silver nitrate (AgNO_3) is:\[ 2 \mathrm{AgNO}_{3}(s) \xrightarrow{heat} 2 \mathrm{Ag}(s) + 2 \mathrm{NO}_{2}(g) + \mathrm{O}_{2}(g) \]This equation shows that when silver nitrate is heated, it decomposes into silver (Ag), nitrogen dioxide (NO_2), and oxygen (O_2).

Step 3: Analyze the Products Formed

From the decomposition equation, the products formed are silver (Ag), nitrogen dioxide (NO_2), and oxygen (O_2). However, only the gaseous products are typically asked for in such problems. Hence, the gaseous products are NO_2 and O_2.

Step 4: Select the Correct Option

Among the given options, (b) NO_2 and O_2 matches the products formed during the thermal decomposition of AgNO_3. Therefore, the correct answer to the problem is option (b).

Key Concepts

Silver Nitrate (AgNO3)

Silver Nitrate, represented by the chemical formula \(AgNO_3\), is a compound well known in chemistry. It is highly soluble in water and commonly used in various chemical reactions. One of its significant traits is its ability to undergo thermal decomposition when subjected to high temperatures. During this process, silver nitrate decomposes to form silver metal, nitrogen dioxide, and oxygen. Understanding silver nitrate is crucial when exploring its reactivity, particularly in the context of thermal decomposition, where the compound breaks down into simpler, more stable products.

Chemical Equation

Chemical equations are foundational in understanding chemical reactions. They symbolize the conversion of reactants into products using symbolic equations. In the context of silver nitrate's thermal decomposition, the balanced equation is:\[2 \mathrm{AgNO}_{3}(s) \xrightarrow{heat} 2 \mathrm{Ag}(s) + 2 \mathrm{NO}_{2}(g) + \mathrm{O}_{2}(g)\]This equation reveals that two moles of silver nitrate decompose into two moles of silver (Ag), two moles of nitrogen dioxide (NO2), and one mole of oxygen (O2). Each component's conservation and transformation are represented, helping you visualize the reaction.

Gaseous Products

During the decomposition of silver nitrate, gaseous products play a pivotal role. They consist of the products that convert into gas form during the reaction. For silver nitrate, the gaseous products include nitrogen dioxide \(NO_2\) and oxygen \(O_2\). These gases are the ones primarily discussed and focused on in chemical reactions due to their volatility and properties, including their effects on the environment and industrial applications. Recognizing gaseous products is important as they might require specific handling, especially in laboratory conditions.

Nitrogen Dioxide (NO2)

Nitrogen Dioxide, abbreviated as \(NO_2\), is a brown gas with significant environmental importance. It is one of the primary gases released during the decomposition of silver nitrate. NO2 is known for its pungent smell and acts as a pollutant in larger concentrations in the atmosphere. Understanding NO2 involves recognizing its role in reactions, its physical properties like being a toxic brown gas, and its applications and effects in both industrial processes and the environment, particularly in air pollution contexts.

Oxygen (O2)

Oxygen is a vital element, represented as \(O_2\), and is crucial for sustaining life and many combustion processes. In the decomposition reaction of silver nitrate, oxygen is one of the gaseous products released. This diatomic molecule plays a crucial role in various scientific endeavors, environmental functions, and industrial applications. Understanding oxygen in this chemical process involves recognizing its properties, its role as a byproduct, and its significance as a reactive and supportive gas in chemical reactions and environmental balance.