MATTER AND ITS PROPERTIES

Matter is anything that has mass, occupies space and can be perceived by our senses. Matter is indestructible, i.e, it can neither be created nor be destroyed. CHARACTERISTICS OF MATTER VOLUME: It is the space occupied by matter MASS: Mass of a body is a quantity of matter contained in that body PERCEPTION: It is something which can be felt by sense of touch, sense of hear, sense of smell, sense of sight and sense of taste. Matter is composed of a particular material and can be homogeneous or heterogeneous. Homogeneous material has the same properties throughout (pure water) Heterogeneous material has different properties throughout(soil, rock) Matter exists in one of the three states namely solid, liquid, and gas. CHARACTERISTIC PROPERTIES OF SOLIDS, LIQUIDS AND GASES PROPERTIES PROPERTIES SOLIDS LIQUIDS GASES 1. SHAPE Definite shape Acquires the shape of the container Acquires the shape of the container 2. VOLUME Definite Definite Indefinite variable 3.COMPRESSIBILITY Not possible Not possible easily Highly compressible 4. FLOW Not possible Possible Possible 5. NUMBER OF FREE SURFACES Any number Onlyone(upper horizantal surfaces None 6. PACKING OF MOLECULES Most closely packed Less closely packed Lease closely packed 7. DENSITY High Low Very low 8. RIGIDITY High Low Not rigid INTERCONVERSION OF STATES OF MATTER The phenomenon of change of one state of mater into another and back to the original state is called the interconversion of states of matter MELTING: Process of changing from solid state to a liquid state at a particular temperature is called melting or fusion. MELTING POINT: The temperature at which a solid becomes liquid is called the melting point. VAPORISATION: Process of change from liquid state to a gaseous state is called vaporization CONDENSATION: Condensation is a process of change from gaseous state to liquid state at a particular temperature. BOILING POINT: The temperature at which a liquid changes into a gas is called boiling point. SOLIDIFICATION : Process of change from liquid state to solid stat at a particular temperature is called freezing or solidification. FREEZING POINT: The temperature at which freezing occurs is called the freezing point. SUBLIMATION: The change of a solid into vapour directly without passing through the liquid state and that of a vapour in to solid directly is called sublimation. heating Solid ________ Vapour Cooling Examples are ammonium chloride, iodine, camphor, naphthalene and solid carbon dioxide etc., change directly into vapour. The solid formed by the vapour of a substance which sublimes is called Sublimate of that substance. EXPERIMENT: Take some crystals of iodine in a test tube and heat them slowly so that the upper part of the tube is not heated. The shiny grey iodine changes to violet vapour without melting. The vapour deposits as grey particles on the upper part of the test tube. The deposit is called the sublimate of iodine. liquid solid gas Water in the solid state(ice) can be changed to liquid form on heating and on further heating above 100C to steam (gaseous state of water) On the other hand stem gets converted in to liquid water when cooled and on further cooling below 0C water changes to solid form (ice) Fusion (melting) evaporation sublimation