Kinetic Particle Theory🥸(Lower sec)

Kinetic Particle Theory 🥸 Also known as Particle Nature Of Matter 1. Particular Nature Of Maer Of Dierent StatesDifferent states of matter have different:→Arrangement of Particles→Movement of Particles→Strength of Attraction characteristics Solid Liquid Gas Arrangement OfParticles - closely packed-arranged in anorderlyarrangement - less closelypacked- arranged in adisorderlymanner - very far apart- arranged in adisorderlymanner Motion OfParticles - Vibrate aboutfixed position - slide over oneanother - more rapidlyin randomdirection AttractionForces BetweenParticles - very strongattractive force - strongattractive force(less strong thansolids) - very weakattractive force Note: All particles are still moving no matter what(even solids!)

a) Why solids have fixed shapes and volumesThe particles of solids are held in fixed positions and do not move out of thosepositions due to strong attractive forces between the particles, hence solids havefixed shapes. Particles of solids are already closely packed and there is no spacefor them to move closer anymore, hence their volume is fixed. b) Why liquids can flowThe particles of liquids are not held in fixed positions and can slide over oneanother easily due to attractive forces between the particles as strong as that insolids. Hence, liquids can flow c) Why gases can be compressedParticles of gases are spread out and have a lot of space between them due tovery weak attractive forces between the particles. Hence, they are able to movecloser together and the gas can be compressed. 2. Expansion and contraction Solids, Liquids and Gases Expansion– when a solid/liquid/gas is heated, particles vibrate more vigorously-distance between particles increase-volume of solid/liquid/gas increases Observable Properties of states of matter(macroscopic) Solid Liquid Gas -Has a fixed shape -has no fixed shape -has no fixed shape -has a fixed volume -has a fixed volume -has no fixed volume -cannot be compressed -cannot be compressed -can be compressed -cannot flow -can flow -can flow

-solid/liquid/gas expands Contraction-When a solid/liquid/gas is cooled, particles lose energy and vibrate lessvigorously-Distance between particles decreases-Volume of solids/liquid/gas decrease-solid/liquid/gas contracts AnsweringTechnique(whydoIstillbelieveinNgan? 😔 )

3.Changes In State MeltingAndBoilingWhen a solid is heated, its particles gain energy and vibrate faster/ morevigorously about its fixed positions. They eventually gain enough energy toovercome the very strong forces of attraction between them. The solid melts andbecomes a liquid. When a liquid is heated, its particles gain energy and slide past one anotherfaster. They eventually gain enough energy to overcome the strong forces ofattraction between them, The liquid boils and becomes a gas.

Freezing And CondensationWhen a liquid is cooled its particles lose energy and slide past one anotherslower. This causes the particles to be pulled much closer to one another by theforces of attraction between them. The particles are eventually held in fixedpositions. The liquid freezes and becomes a solid. When a gas is cooled. Its particles lose energy and move slower. This causes theparticles to be pulled closer to one another by forces of attraction between them.The gas condenses and becomes a liquid. The Heating Curve A pure substance melts and boils at a constant(fixed) temperature at a givenpressure.An impure substance melts and boils over a range of temperatures at a givenpressure.

4. Diusion Factorsaffectingtherateofdiffusion 1. TemperatureThehigherthetemperature, thehighertherateofdiffusion. Particlesgainmoreenergy as thetemp. Increases. They movefasterandthisincreasestherateofdiffusion2. Relativemolecularmass(M ᵣ ) ofagasGaseswithlowerrelativemolecularmassdiffusefaster Itiscalculatedby summinguptherelativemolecularmassoftheelements(eg.water vapour, H ₂ O=1×2+16=18) - Impuritiescauseadecreaseinmeltingpointandincreaseinboilingpointofimpure substances.