Problem 197 - A Complete Resource Book in Chemistry for JEE Main

Question

Match the catalysts to the correct processe Catalyst Process a. \(\mathrm{TiCl}_{3}\) (i) Wacker process b. \(\mathrm{PdCl}_{2}\) (ii) Ziegler-Natta polymerization c. \(\mathrm{CuCl}_{2}\) (iii) Contact process d. \(\mathrm{V}_{2} \mathrm{O}_{5}\) (iv) Deacon's process (a) a (iii), b (ii), c (iv), d (i) (b) a (ii), b (i), c (iv), d (iii) (c) a (ii), b (iii), c (iv), d (i) (d) a (iii), b (i), c (ii), d (iv)

Step-by-Step Solution

Answer

Option (b) a (ii), b (i), c (iv), d (iii) is correct.

Step 1: Identify each catalyst with its process

First, match each catalyst with its well-known chemical process. 1. \( \text{TiCl}_3 \) is commonly used in the Ziegler-Natta polymerization process, which is a method for producing polyethylene and polypropylene.2. \( \text{PdCl}_2 \) is associated with the Wacker process, which is utilized in the oxidation of ethylene to acetaldehyde.3. \( \text{CuCl}_2 \) is used in the Deacon's process, which is a method for producing chlorine by the oxidation of hydrogen chloride.4. \( \text{V}_2 \mathrm{O}_{5} \) is known for its role in the Contact process, particularly in the oxidation of sulfur dioxide to sulfur trioxide.

Step 2: Match catalysts to processes

Using the identified matches from Step 1, we can pair each catalyst with the appropriate process:- \( \text{TiCl}_3 \) matches with process (ii), Ziegler-Natta polymerization.- \( \text{PdCl}_2 \) matches with process (i), Wacker process.- \( \text{CuCl}_2 \) matches with process (iv), Deacon's process.- \( \text{V}_2 \mathrm{O}_{5} \) matches with process (iii), Contact process.

Step 3: Find the correct answer from the options

Now, compare the matching of catalysts to processes with the provided options:- Option (a): a (iii), b (ii), c (iv), d (i) - Option (b): a (ii), b (i), c (iv), d (iii) - Option (c): a (ii), b (iii), c (iv), d (i) - Option (d): a (iii), b (i), c (ii), d (iv) The correct sequence based on our matching is found in option (b): \( a(ii), b(i), c(iv), d(iii) \).

Key Concepts

Wacker Process

The Wacker Process is an important industrial catalytic process used to oxidize ethylene to acetaldehyde. The key catalyst used in this process is

• Palladium chloride \( \mathrm{PdCl}_2 \): This strong catalyst is reduced by ethylene to metallic palladium, and then reoxidized to \( \mathrm{PdCl}_2 \) by \( \mathrm{CuCl}_2 \,\) completing the cycle.

This two-step cycle ensures the continuous flow of the process.
The reaction takes place in an aqueous medium and efficiently converts ethylene (\( \mathrm{C}_2\mathrm{H}_4 \) ) to acetaldehyde (\( \mathrm{CH}_3CHO\) ). Another feature of the Wacker process is its relatively low requirement for energy compared to similar oxidation reactions.
This makes it economically viable and environmentally friendly.

Ziegler-Natta Polymerization

Ziegler-Natta Polymerization is a crucial process in the manufacturing of polyethylene and polypropylene. It's named after the chemists Karl Ziegler and Giulio Natta, who were instrumental in developing these catalytic systems.

• Titanium trichloride \( \mathrm{TiCl}_3 \): This catalyst works in concert with organoaluminum compounds like triethylaluminum, enabling the polymerization of simple alkenes into long polymer chains.

The process allows for the production of polymers with specific orientations and properties, significantly enhancing their industrial applications.
This method changed the plastic industry by allowing control over the stereochemistry of the polymer, resulting in polymers with increased strength and clarity.

Contact Process

The Contact Process is a method of producing sulfuric acid in high concentrations, which is vital for various industrial processes. The catalyst used here is:

• Vanadium(V) oxide \( \mathrm{V}_2 \mathrm{O}_5 \): It plays a crucial role in oxidizing sulfur dioxide to sulfur trioxide, which is then used to synthesize sulfuric acid.

This method allows for the continuous production with high yield and has largely replaced older methods due to its efficiency.
In the Contact Process, the reaction occurs in a hot gas phase. The sulfur dioxide is first oxidized to sulfur trioxide over the vanadium oxide catalyst at around 450°C, maximizing the conversion rate through optimal conditions. The resulting sulfur trioxide is then absorbed in water to produce sulfuric acid, specifically maintaining control to avoid excessive heat and energy loss.

Deacon's Process

Deacon's Process is an older industrial method for producing chlorine gas from hydrogen chloride, typically as a byproduct of hydrochloric acid production. The catalyst associated is:

• Copper(II) chloride \( \mathrm{CuCl}_2 \): This compound catalyzes the oxidation of \( \mathrm{HCl} \,\) regenerating chlorine in the presence of atmospheric oxygen.

Although now largely supplanted by more modern methods, the Deacon's Process was influential in its heyday.
In this reaction, hydrogen chloride gas reacts with oxygen to produce water and chlorine gas with the help of the copper chloride catalyst.
The process emphasizes reutilizing hydrogen chloride, remarkably integrating the recycling of chemical waste into usable products.