Matter (audio) r1

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Structure of Matter What is Matter?

Transcript of Matter (audio) r1

  • 1.Structure of MatterWhat is Matter?

2. Everything in the Universe can be classified as either matter or energy! So what is matter? Define matter: Matter is anything that has mass and occupies avolume.Matter is the stuff the Universe is made ofA Kaboom Key Concept!1. All matter is composed of very tiny particlesThis is the first statement of the Particle Model of Matter.2. Particles are in constant motion.3. Particles have spaces between them. The spaces are much larger than the particles themselves.4. Particles are attracted to each other by electrostatic forces. 2 3. Particles are in constant motion . . .The energy of the particles in matter determines particle motion andaffects the how far apart the particles are from each other.We can think of particle energy as TEMPERATURE. As temperature increases, the average energy of the particles increasesThe temperature determinesthe phase or state of the matter 3 4. Three Phases of MatterDJY - Chemistry I 4 5. Adding heat allows particles to overcome theattractive forces that pull them together.Add heat 5 6. Solids definite volume and shape; particles packed infixed positions; particles can vibrate back and forth only 6 7. Liquids definite volume but indefinite shape; particlesclose together but not in fixed positions; particles arefree to move (rotate) DJY - Chemistry I7 8. Gases neither definite volume nor definite shape;particles are at great distances from one another;particles are free to move (translate)DJY - Chemistry I 8 9. Plasma a plasma is an ionized gas. Plasma shares similar characteristics to gases.A plasma is also a very good conductor of electricity andis affected by magnetic fields.9 10. Heating Curve for Water (a pure substance)Water phase changes constantTemperature remains __________during a phase change.DJY - Chemistry I 10 11. Phase change diagramVaporizationor boiling ExothermicEndothermic (heat released) (heat absorbed) 11 12. Physical changes . . .change a substance WITHOUTchanging its chemical makeup.After a physical change, you still havethe same substance, it is just in adifferent form.Examples:boiling, freezing, melting, condensationdissolvingsplit, crack, crush etc 12 13. Physical properties ..are qualities which can be observed withoutchanging the substances composition.For example:boiling point, freezing point, melting pointcolorhardnessdensitymalleability, ductilitysolubility conductivity 13 14. Chemical changes Substances are broken down in chemical reactions and new substances are made.Example - Burning hydrogen(H2) with oxygen (O2) givesH2O.14 15. Chemical Propertiesdescribe the howsubstances react chemically. For example: Metals react in acid to produce H2 gas Zn (s) + HCl (aq) H2 (g) + ZnCl2 (aq) DJY - Chemistry I 15 16. In a CHEMICAL CHANGE, the composition of theoriginal substance(s) is altered.The process of chemical change is described as achemical reaction. chemical changeREACTANTSPRODUCTSDifferent substances are present at the end of thechemical change. The atoms in the reactants arerearranged to make new and different products. 16 17. Signs of a Chemical Change Color change Heat Light Gas Produced (not from boiling!) Precipitate a solid formed by mixingtwo liquids togetherDJY - Chemistry I17 18. Physical vs. Chemical PropertiesExamples melting point flammable density magnetic tarnishes in air 18 19. Physical vs. Chemical PropertiesExamples melting pointphysical flammablechemical densityphysical magnetic physical tarnishes in air chemical 19 20. Physical vs. Chemical Changes Examples: rusting iron dissolving in water burning wood melting ice grinding spices20 21. Physical vs. Chemical Changes Examples: rusting ironchemical dissolving in water physical burning woodchemical melting ice physical grinding spices physical 21