CBSE NCERT Science Class 9 Chapter 1: Matter in Our Surroundings
Chapter 1: Matter in Our Surroundings Notes: 1. Matter: - Everything around us is made up of matter. Matter is anything that has mass and occupies space. - It can be classified into three states: solid, liquid, and gas, based on the arrangement and movement of particles. 2. Characteristics of Particles of Matter: - Particles of matter are very small and are constantly moving. - They have spaces between them, and these spaces increase on heating. - The particles attract each other, and the force of attraction is maximum in solids and minimum in gases. 3. States of Matter: a. Solid: - Solids have a definite shape and volume. - The particles are closely packed in an orderly manner. - They have fixed positions and vibrate around their mean positions. - Solids cannot be compressed much. b. Liquid: - Liquids have a definite volume but no fixed shape. - The particles in liquids are closely packed but can move around each other. - They can flow and take the shape of the container they are pou
