Question

The adsorption of large volumes of hydrogen by metal such as palladium is known as (1) Dehydrogenation (2) IIydrogcnation (3) Occlusion (4) Adsorption

Short answer

The correct answer is (3) Occlusion.

Step-by-step solution

Understand the Terminology

First, review the terms given in the choices: Dehydrogenation, Hydrogenation, Occlusion, and Adsorption. It's essential to understand each term's definition and implications in chemistry.

Definition of Terms

1. Dehydrogenation: The removal of hydrogen from a molecule.2. Hydrogenation: The addition of hydrogen to a molecule.3. Occlusion: The absorption of gas molecules into a solid.4. Adsorption: The adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface.

Apply the Concept

For this exercise, the process involves the absorption of a large volume of hydrogen by a metal. Evaluate which term best describes this process based on the definitions.

Choose the Correct Answer

The process that involves the absorption of a large volume of hydrogen by palladium is best described by 'occlusion,' which refers to gas molecules being absorbed by a solid.

Key concepts

Adsorption

Adsorption is a crucial concept in chemistry involving the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface. Unlike absorption, where a substance diffuses into a liquid or solid to form a solution, adsorption involves particles adhering only to the surface. This process is important for various applications like catalysis, where catalysts provide a surface for reactants to adhere and react more readily. It's helpful to imagine a sponge; while a sponge absorbs water (the water enters the sponge), adsorption is more like dust collecting on the surface of the sponge.

Dehydrogenation

Dehydrogenation is a chemical reaction that involves the removal of hydrogen from a molecule. This process is typically used in the petrochemical industry to convert alkanes to alkenes. For example, converting ethane into ethylene involves removing hydrogen atoms. Dehydrogenation reactions are crucial for processes like the production of olefins and aromatic hydrocarbons. This reaction usually requires an endothermic process, which means it needs heat to proceed. Catalysts are often used to help speed up dehydrogenation reactions and to make the process more energy-efficient.

Hydrogenation

Hydrogenation is the process of adding hydrogen to another compound, typically in the presence of a catalyst. This reaction is often used to convert unsaturated fats to saturated fats in the food industry. For example, converting vegetable oil into margarine involves hydrogenation. In addition to making fats more solid at room temperature, hydrogenation also increases the stability and shelf life of food products. In the petrochemical industry, hydrogenation is used to reduce alkenes and alkynes into alkanes, rendering them less reactive and more stable.

Gas Absorption by Metals

Gas absorption by metals, also known as occlusion, involves the uptake of gas molecules into a solid, such as a metal. Certain metals like palladium have the unique ability to absorb large volumes of gases like hydrogen. This is particularly useful in hydrogen storage for fuel cells, where the metal acts as a sponge for hydrogen gas. The absorbed gas can then be released when needed. Occlusion is different from adsorption; while adsorption involves particles sticking to the surface, occlusion involves the gas molecules being incorporated into the solid material itself. This property of metals like palladium is exploited in various industrial applications, including catalysis and hydrogen purification.