What is Vapour and Gas: Introduction
To explain vapour and gas: Understanding the states of matter is crucial in studying chemistry. Matter can exist in three primary states: solid, liquid, and gas. However, within the gaseous state, two terms are often used interchangeably: vapour and gas. Understanding the characteristics of vapour and gas is a big part of chemistry, and it's essential for students studying for tests like NEET and JEE. In this article, we'll look at some of the most important differences between vapour and gas.
Defining Soap:
Vapour refers to the gaseous state of a substance that is typically found as a liquid or solid at room temperature and atmospheric pressure. It is formed when a substance undergoes evaporation or sublimation. Evaporation occurs when a liquid changes into a gas at temperatures below its boiling point, while sublimation is the direct conversion of a solid into a gas without passing through the liquid phase.
Characteristics of Vapour:
Formation: Vapour is specifically formed from substances that have a boiling point or sublimation point below the current temperature and pressure conditions.
Composition: Vapour retains the same chemical composition as the liquid or solid from which it originated.
Condensation: Vapour can condense back into its liquid or solid state when it comes into contact with a cooler surface or when the temperature and pressure conditions change.
Density: Vapours generally have a lower density compared to gases since they are often formed from liquids or solids that are denser than gases.
Visibility: Vapours are often visible, appearing as clouds or fog due to the presence of tiny liquid or solid particles within them.
Defining Detergent:
Gas refers to the gaseous state of matter, which can be found at room temperature and atmospheric pressure or obtained by heating a solid or vaporising a liquid. Unlike vapour, gases do not necessarily originate from liquids or solids and can exist independently.
Characteristics of Gas:
Origin: Gases can be obtained from various sources, including evaporation, sublimation, combustion, or directly from chemical reactions.
Composition: Gases can consist of individual atoms or molecules and may have a different composition than the substances from which they are derived.
Expansion: Gases have the ability to expand to fill the available space uniformly.
Compressibility: Gases are highly compressible, meaning their volume can be significantly reduced under increased pressure.
Homogeneity: Gases exhibit a high degree of homogeneity, with their constituent particles being evenly distributed throughout.
Vapour and Gas Difference
Summary
Vapour and gas are two terms used to describe the gaseous state of matter. Vapour refers to the gaseous state of a substance that is usually a liquid or solid at room temperature, while gas is a more general term that can include substances that exist in the gaseous state independently. Vapours have a specific origin and composition, while gases can originate from various sources and have different compositions. vapours can condense back into their liquid or solid state, while gases lack this ability under normal conditions. Furthermore, vapours can be visible and may contain liquid or solid particles, while gases are typically invisible and homogeneous. Finally, vapours have a lower density and are less compressible compared to gases. Understanding these differences is essential for a comprehensive understanding of the gaseous state of matter in the context of class 12 chemistry.
FAQs on Difference Between Vapour and Gas for JEE Main 2024
1. What causes the formation of vapour?
Vapour is formed when a substance undergoes evaporation or sublimation. Evaporation occurs when a liquid changes into a gas at temperatures below its boiling point, while sublimation is the direct conversion of a solid into a gas without passing through the liquid phase.
2. Can gases be visible like vapours?
Gases are generally invisible under normal conditions. However, gases can become visible if they contain impurities or undergo reactions that lead to the formation of visible particles, such as smoke or fog.
3. Explain the difference between vapour and gas in terms of density?
Vapour and gas differ in terms of their density. Vapour, which is the gaseous state of substances usually found as liquids or solids, tends to have lower density compared to gases. Vapours are formed when substances undergo evaporation or sublimation, resulting in gaseous particles that are more spread out and have less mass per unit volume compared to the original substance. For example, when liquid water evaporates, the water vapour has a lower density than the liquid water due to the increased spacing between water molecules. On the other hand, gases can have varying densities depending on the specific gas and its constituent particles. Some gases, like helium or hydrogen, have very low densities due to their light particles and greater dispersion. In contrast, gases such as carbon dioxide or nitrogen have higher densities because their particles are heavier. In summary, vapour generally has a lower density than gases, as it is formed from denser substances, while gases can have different densities depending on their composition and particle mass.
4. Explain vapour and gas reactions with Ability to Condense.
Vapour and gas exhibit contrasting abilities to condense. Vapour, which refers to the gaseous state of substances that are typically liquids or solids at room temperature and atmospheric pressure, can condense back into their liquid or solid form. When a vapour encounters cooler temperatures or a change in pressure, it releases energy and undergoes condensation, transitioning from the gaseous state to the liquid or solid state. This condensation process is specific to vapours and is influenced by their origin as liquids or solids. For instance, water vapour can condense into liquid water upon contact with a cooler surface, forming droplets or mist. In contrast, gases lack the inherent ability to condense under normal conditions. Gases, which can exist independently and are not tied to specific substances, do not readily condense into liquids or solids without external factors such as cooling or increased pressure. Although gases do not naturally undergo condensation, they can be liquefied or solidified through processes involving the manipulation of temperature and pressure. In summary, vapour possesses the intrinsic capacity to condense, while gases require external influences to transition into liquids or solids.
5. Concisely describe the vapour and gas difference with the help of the origin.
Vapour and gas differ significantly in terms of their origin. Vapour refers to the gaseous state of a substance that is typically a liquid or solid at room temperature and atmospheric pressure. It is formed through processes such as evaporation or sublimation. Evaporation occurs when a liquid changes into a gas at temperatures below its boiling point, while sublimation is the direct conversion of a solid into a gas without passing through the liquid phase.
