Matter in Our Surroundings Lecture -4 Class 9 Science Term -1 CBSE Free Education

Class 09 Preparation #Class09Chemistry #matterinoursurroundingsclass9 Matter in Our Surroundings : CBSE Class 09 IX Science (Chemistry). Let's watch this amazing topic - Matter in Our Surroundings for your effective Board Exam - Chemistry Preparation with proper explanation by your favorite teacher. In this session, you will find Tips, Tricks, and Strategies in detail to score full marks in class 09 Chemistry. So, Don't Miss It!! 👉 Do watch the complete session to know about the Chemical Reactions and Equations, Don't forget to share this video with your friends and classmates. ✴️✔️ Do 𝐒𝐔𝐁𝐒𝐂𝐑𝐈𝐁𝐄 to the channel for more updates and hit that like button! ❤️ for daily Updates : (Turn on your notification 🔔 to get all updates before anyone!!) Understanding Temperature Measurement and State Changes in Matter Introduction In this Lecture, we will explore the concepts of temperature measurement, the devices used for it, and the changes in states of matter. The discussion will cover the use of thermometers, the significance of temperature units like Celsius and Kelvin, and the processes of state changes due to temperature and pressure. Temperature Measurement Thermometer: A device used to measure temperature. Commonly used in households, especially when checking for fever. Temperature Units: Celsius (°C): The most commonly used unit in daily life. For example, a normal human body temperature is approximately 36.8°C. Kelvin (K): The SI unit of temperature, used primarily in scientific contexts. The conversion from Celsius to Kelvin is done using the formula: Temperature in Kelvin = Temperature in Celsius + 273 | Temperature in Celsius | Temperature in Kelvin | |--------------------------|-------------------------| | 25°C | 298 K | | 100°C | 373 K | Understanding Temperature Readings A thermometer reading of 36.8°C indicates a normal body temperature. Higher temperatures indicate heat, while lower temperatures indicate cold. Different cities report varying temperatures, e.g., New Delhi at 26°C and Lucknow at 30°C. State Changes of Matter States of Matter: Matter can exist in different states: solid, liquid, and gas. For example, water can exist as ice (solid), water (liquid), or steam (gas). Change of State: The transition between these states can occur due to temperature changes or pressure changes. Temperature-Induced State Changes 1. Melting: The process where a solid turns into a liquid (e.g., ice melting into water at 0°C). 2. Vaporization: The process where a liquid turns into a gas (e.g., water boiling into steam at 100°C). 3. Freezing: The process where a liquid turns into a solid (e.g., water freezing into ice). 4. Condensation: The process where a gas turns into a liquid (e.g., steam condensing into water). Important Points on State Changes Melting Point: The temperature at which a solid changes to a liquid. For ice, it is 0°C. Boiling Point: The temperature at which a liquid changes to a gas. For water, it is 100°C. During state changes, the temperature remains constant even when heat is applied. This is due to the energy being used to overcome the forces of attraction between particles. Pressure-Induced State Changes Pressure Application: Increasing pressure can compress gases, leading to a change in state. Gas to Liquid: When pressure is applied to a gas, it can condense into a liquid. Gas to Solid: In some cases, gases can directly convert into solids under high pressure, a process known as sublimation. Sublimation Definition: The process where a solid changes directly into a gas without passing through the liquid state (e.g., dry ice). Examples: Naphthalene balls: Used in homes to prevent insect infestation; they sublimate and disappear over time. Camphor: Burns and sublimates directly into vapor. Conclusion Understanding temperature measurement and the changes in states of matter is crucial in both everyday life and scientific applications. The use of thermometers, the significance of temperature units, and the processes of melting, boiling, and sublimation illustrate the dynamic nature of matter. By grasping these concepts, students can better appreciate the physical world around them and the principles governing it. Let us know your doubts regarding today's topic "Matter in Our Surroundings Lecture -1: CBSE Class 9 Science (Chemistry) -" in the comment below 👇 we will respond to solve your doubts asap. See you guys in the ⏭️ next surprising session! Till then stay tuned...