Problem 11 - 43 Years JEE ADVANCED (1978-2020) + JEE MAIN Chapterwise & Topicwise Solved Papers Chemistry

Question

The acid having \(\mathrm{O}-\mathrm{O}\) bond is [2004S] (a) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{3}\) (b) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{6}\) (c) \(\mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{8}\) Page \(543 / 1,773-\mathbb{Q}\) ? (d) \(\mathrm{H}_{2} \mathrm{~S}_{4} \mathrm{O}_{6}\)

Step-by-Step Solution

Answer

The acid with the \( \mathrm{O}-\mathrm{O} \) bond is \( \mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{8} \).

Step 1: Identify the Structures

Understand the structure of each acid. For example, \( \mathrm{H}_2\mathrm{S}_2\mathrm{O}_3 \) (thiosulfuric acid) does not have a \( \mathrm{O}-\mathrm{O} \) bond.

Step 2: Examine Options

Evaluate each given option: - **\( \mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{3} \):** Contains no \( \mathrm{O}-\mathrm{O} \) bonds. - **\( \mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{6} \):** Dithionic acid, also lacks an \( \mathrm{O}-\mathrm{O} \) bond.- **\( \mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{8} \):** Known as peroxydisulfuric acid, this contains an \( \mathrm{O}-\mathrm{O} \) bond.- **\( \mathrm{H}_{2} \mathrm{~S}_{4} \mathrm{O}_{6} \):** Tetrathionic acid, no \( \mathrm{O}-\mathrm{O} \) bond present.

Step 3: Identify the Correct Acid

From the evaluation in Step 2, \( \mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{8} \) is the only acid with an \( \mathrm{O}-\mathrm{O} \) bond.

Key Concepts

Peroxydisulfuric Acid

Peroxydisulfuric acid is a fascinating compound, known scientifically as \( \mathrm{H}_{2} \mathrm{~S}_{2} \mathrm{O}_{8} \). This compound is part of a family of sulfuric acid derivatives. Its structure includes a unique \( \mathrm{O}-\mathrm{O} \) bond, distinguishing it from many other sulfuric acids.

Peroxydisulfuric acid is often involved in industrial and chemical applications. It acts as an oxidizing agent due to its ability to donate oxygen. The presence of the \( \mathrm{O}-\mathrm{O} \) peroxide linkage is key to its oxidizing properties.

In aqueous solutions, peroxydisulfuric acid tends to decompose, releasing oxygen and forming simpler acids such as sulfuric acid. This behavior highlights its role in processes where controlled oxidation is necessary.

O-O Bond

The \( \mathrm{O}-\mathrm{O} \) bond, commonly known as a peroxide bond, is a bond where two oxygen atoms are directly connected. This type of bond is rare among naturally occurring molecules due to its inherent instability.

Here are some important points regarding the \( \mathrm{O}-\mathrm{O} \) bond:

• It is typically found in peroxides, such as hydrogen peroxide (\( \mathrm{H}_2 \mathrm{O}_2 \)).
• The bond is weak compared to other single bonds, making it more reactive and less stable.
• Compounds with \( \mathrm{O}-\mathrm{O} \) bonds are often used as bleaching agents or disinfectants due to their reactive nature.

In the case of peroxydisulfuric acid, the \( \mathrm{O}-\mathrm{O} \) bond is crucial for its oxidizing capability, enabling the compound to aid in processes that require the transfer of oxygen atoms.

Sulfuric Acid Derivatives

Sulfuric acid derivatives are a group of chemicals derived from sulfuric acid, \( \mathrm{H}_2\mathrm{SO}_4 \), known for their wide range of applications. These derivatives can retain some similar properties to sulfuric acid but often have additional features due to structural modifications.

Common derivatives include:

• Peroxydisulfuric Acid (\( \mathrm{H}_2 \mathrm{~S}_2 \mathrm{O}_8 \)): Known for its oxidizing properties due to the \( \mathrm{O}-\mathrm{O} \) bond.
• Thiosulfuric Acid (\( \mathrm{H}_2 \mathrm{~S}_2 \mathrm{O}_3 \)): Includes a sulfur-sulfur bond, rather than an oxygen-oxygen bond.
• Dithionic Acid (\( \mathrm{H}_2 \mathrm{~S}_2 \mathrm{O}_6 \)): This contains a more complex structure, without the \( \mathrm{O}-\mathrm{O} \) bond.

Sulfuric acid derivatives are pivotal in the chemical industry not only because of their versatility but also due to the distinct chemical properties derived from their unique structural components.