Presentation on theme: "Matter, Forces, Energy, Motion and Heat"— Presentation transcript:
1 Matter, Forces, Energy, Motion and Heat 8th GRADE PHYSICSMatter, Forces, Energy, Motion and Heat
2 READ TO STUDENTS: ALL MATTER IS COMPOSED OF ATOMS; THERE ARE OVER KNOWN 100 ELEMENTS THAT CAN BOND AND FORM COUNTLESS COMPOUNDS. REMEMBER: AN ATOM IS THE SMALLEST PART OF AN ELEMENT THAT STILL MAINTAINS ALL OF THE PROPERTIES 0F THAT ELEMENTSECTION 1: MATTER
3 Important TermsChemistry- The study of the properties of matter and how matter changes.Substance- A single kind of matter that is pure and has a specific set of properties.Mixture-Two or more substances that are mixed together but not chemically combined.Mixtures can be heterogeneous or homogeneous
4 DESCRIBING MATTER Question: What is matter? Answer: Anything that has mass and takes up spaceAll matter is composed of atomsAtom- The basic particle from which all elements are madeElement- A pure substance that cannot be broken down into other substances by chemical or physical means.
5 Chemical Bond- The force that holds two atoms together Molecule- A particle made of two or more atoms bonded togetherCompound- A pure substance made of two or more different elements chemically combinedchemical formula- A formula that gives the elements in a compound and the ratio of atomsExample: H2O C6H4O2Fe5IF THE RATIO OF THE ELEMENTS CHANGES THEN IT IS NO LONGER THAT COMPOUND. FOR EXAMPLE, WATER HAS A RATIO OF 2 HYDROGEN ATOMS FOR EVERY ONE OXYGEN ATOM. IF THE RATIO WAS CHANGED FROM 2:1 TO 3:1, YOU WOULD NO LONGER HAVE WATER
6 COMPOUNDS VS. MOLECULES NOTE: ALL COMPOUNDS ARE MOLECULES BUT NOT ALL MOLECULES ARE COMPOUNDS
7 Matter has both physical and chemical properties
8 Properties of Matter Physical Property Examples Chemical Property Examplesphysical property- A characteristic of a pure substance that can be observed without changing it into another substanceColorSizeShapeMassDensityVolumeTexturechemical property- A characteristic of a pure substance that describes its ability to change into a different substanceReactivitypH (is it an acid or a base)FlammabilityToxicityOxidation statesHeat of combustion
9 MEASURING MATTER Tools of Measurement: Mass: scale or triple beam balanceLength: rulerVolume:For a regular shaped object use the formula LxWxHFor a irregularly shaped object use water displacementDensityD=M/V
10 Density of a regular shaped object This block of wood has the following measurementsL= 10cmW= 2cmH= 5cmMass= 50 gIn your notebook, calculate the volume, then find the density. Remember to label the unitsV= LxWxH V= 10x5x2= 100cm 3 D=M/V D=50/100= 0.5g/cm3
11 Density of an irregularly shaped object Toy DinosaurMass= 2mgVolume= volume with object- volume without objectV=5.8mL-4.8mL= 1mLWhat is the density or the toy dinosaur?D=M/VD=2mg/1mL = 2mg/mLNOTE: 1mL=1cm3
12 CHANGES IN MATTER Matter can undergo physical and chemical changes Physical Change- A change in a substance that does not change its identityExamples: changing shape, form, state of matterChemical Change- A change in which one or more substances combine or break apart to form new substancesExamples: burning, oxidation, combustion, tarnishing, electrolysis
16 ENERGY IN MATTER Key Terms: Kinetic Energy- The energy of matter in motionPotential Energy- The energy an object has because of its position; also the internal stored energy of an object, such as energy stored in chemical bonds
17 Forms of EnergyChemical Energy- A form of potential energy that is stored in chemical bonds between atomsElectromagnetic Energy- A form of energy that travels through space as wavesElectrical Energy- The energy of electrically charged particles moving from one place to another.