2 Particle Theory of Matter 1. All matter is made up of tiny particles.2. These particles are always moving… they have energy.3. There are spaces among particles.4. There are attractive forces between the particles.5. The particles of one substance differ from the particles of other substances.
3 We can classify matter as: a pure substance or as a mixture. Classifying MatterWe can classify matter as:a pure substance oras a mixture.
4 Mixtures + = Sugar Water Mixtures contain two or more different kinds of particles.MAY appear the same throughoutMAY have distinct visible parts+=Sugar and waterSugarWater
5 Examples of Mixtures… salt water, Kool-Aid chocolate chip cookie muddy watersalad dressingair
6 Pure Substances...Pure substances are made up of only one type of particle and therefore look the same all throughout.
7 Examples of Pure Substances sugar (C12H22O11)gold (Au), copper (Cu)distilled water (H2O)carbon dioxide (CO2)oxygen (O2)
8 Mixtures: Mixtures may be: Homogeneous (also called solutions) Or Heterogeneous (also called mechanical mixtures)
9 Homogeneous MixturesThese mixtures appear to be the same throughout and often have the same properties:-only one part visible (appears to be one substance)-usually transparent-light passes through unaffected- particles do not settle, they dissolve
10 the particles are evenly mixed so that none of the original substances are visible (dissolved) Kool-aid
11 Homogeneous Mixture can be: solid liquid or gas Stainless steel Salt waterClean air
12 More Examples of Homogeneous Mixtures Apple juiceKool aidSalt waterStainless steelBrassClean air
13 Heterogeneous Mixtures Have different visible parts, each with their own properties- two or more parts visible to the eye- not transparent- particles settle and they do not evenly mix-Light will scatter
14 Heterogeneous Mixtures can include:solidsliquidsorgasesGranola barOil and vinegarPolluted air
15 Examples of Heterogeneous Mixtures Sand and waterGranola barTossed saladPizzaCementPolluted airOil and vinegarSalad dressing
16 Homogeneous or Heterogeneous 3 techniques can be used to distinguish between the two:Use a microscope. A solution contains only one type of particleUse a filter. If anything gets caught in the filter it is a mechanical mixture.Tyndall effect. Mixtures scatter the light (you can see it ) and solutions do not scatter light (you cannot see it).
17 Tyndall EffectThe tyndall effect can be used to tell the difference between a solution and a mixture.cannot be used to distinguish between a solution and a pure liquidHow?If you shine a beam of light directly through a mixture and you do not see the beam, it is probably a solution. The particles are evenly mixed at the molecular level so they will not block or scatter the light.Left: Silver colloid mixtureRight: Tap water
18 In a Solution...Light passes unaffected (if a student looks at the beaker perpendicular to the direction of the beam they will NOT see it
19 In a Mechanical Mixture... The light will scatter as it passes through the mixture because all particles are not dissolved (as shown on the left)
21 Flow Chart Matter Pure Mixture Heterogeneous Homogeneous Mechanical Solutionmixture
22 Some mixtures may be both homogeneous and heterogeneous Example: orange juiceThe large pulp particles make it a heterogeneous and the sugar molecules dissolved in it make it homogeneous.
23 ColloidsA colloid is a type of mixture that appears to be a solution but it is actually a mechanical mixture
24 Solid Sol Examples: cranberry glass, ruby glass Examples of colloidsDispersed mediumGasLiquidSolidContinuousMedium GasNONE (All gases are mutually miscible)Liquid Aerosol Examples: fog, mistSolid aerosol Examples: smoke, air particulatesFoam Examples: whipped creamEmulsion Examples: mayonnaise, hand creamSol Examples: milk, paint, pigmented inkSolid Foam Examples: aerogel, styrofoam, pumiceGel Examples: butter, gelatin, jelly, cheese, opalSolid Sol Examples: cranberry glass, ruby glass
25 SuspensionsSuspensions are a heterogenous fluid containing solid particles will settle over time if left undisturbedExamples:Mud or muddy water, is where soil, clay, or silt particles are suspended in water.Flour suspended in waterFog is water suspended in air.PaintChalk powder suspended in water.Dust particles suspended in air.