Matter chapter 3

Matter massspace anything that has mass & occupies space –mass: gramskilograms –mass: measured in grams or kilograms volumeliterscm 3 –space/volume: measured in liters or cm 3

Phases SOLIDS LIQUIDS GASES

solid: solid: definite volume definite shape

liquid definite volume indefinite shape takes the shape of container

gas indefinite volume indefinite shape takes the shape and volume of container

States of Matter 1.How are the particles packed in each phase? 2.How do the particles move in each phase? 3.Why do liquids and gases flow? 4.Why are gases so easy to compress?

4 th phase of matter plasmaplasma exists in stars e lectrons are stripped from atoms

Physical Properties describe appearance & form of matter descriptive words: color, texture, luster, odor solid, liquid, gasmeasurements: a number and a unit

Intensive properties –Physical Constants –independent –independent of sample size –amount doesn’t matter density, freezing point, and melting point solubility in water (g/ml)

Extensive Properties extensive properties:extensive properties: mmass  volume depend on sample size: amount) mattersquantity (amount) matters

Chemical Properties describe how matter: behaves in presence of other matter changes into another kind of matter examples: –flammability –resistance to corrosion –ability to neutralize acids or bases

Properties of Copper Physical Prop. reddish brown shiny Malleable ductile good conductor density = 8.92 g/cm 3 mp = 1085  C bp = 2570  C Chemical Prop. reacts to form green copper carbonate forms deep blue solution when in contact with NH 3 forms new substances with HNO 3

Physical Change identityform or appearance of matter may change but identity remains same –cutting, crushing, grinding,tearing phase changesdissolving

Dissolving dissolving is physical change: think of putting sugar in water still have sugar – sugar molecules just spread out between water molecules C 6 H 12 O 6 (s)  C 6 H 12 O 6 (aq)

Phase Changes phase changes are physical changes no new substance is created (chemical formula stays the same) Ex: ice melting: H 2 O(s)  H 2 O(l) water boiling: H 2 O (l)  H 2 O(g)

Chemical Change chemical change - identity of matter is changed new substance with own unique properties is formed chemical formula changes Ex: 2H 2 O(l)  2H 2 (g) + O 2 (g)

Burning oxidation reactioncommon name for oxidation reaction indicates matter reacting with oxygen is chemical change - original substance is changed into new kind(s) of matter Ex: CH 4 (g) + 2O 2 (g)  CO 2 (g) + 2H 2 O(g)

Evidence of Chemical Change 1.bubbling [formation of a gas] 2. color change 3.heat [gets colder or hotter] 4. light produced 5.formation of a solid [2 liquids mix and solid is formed - this is a precipitate(ppt)]

What kinds of matter are there?

Matter SubstancesMixtures Elements Compounds Heterogeneous Mixtures Homogeneous Mixtures mixtures  separated by physical methods compounds  separated by chemical methods

Element substance that: cannot be broken down (decomposed) into simpler substance only 1 kind of atom has definite properties formulas have 1 uppercase letter

Element Song

Atom smallest particle of element that retains properties of element smallest particles of element that can undergo a chemical reaction

Compounds 2 or more DIFFERENT elements chemically combined in a definite ratio differentproperties of compound are different from properties of elements formed from homogeneous in composition separated into elements by chemical decomposition reaction formulas have 2 or more uppercase letters

2Na + Cl 2  2NaCl Na(s) Cl(g) NaCl(s)

Mixtures combo of 2 or more pure substances NOTphysically combined NOT chemically combined each substance retains its own identity and properties

Mixtures variable composition no unique properties (think of sugar and sand mixed together) physical methodsseparated by physical methods may be homogeneous or heterogeneous

Types of Mixtures

homogeneous: constant composition throughout single phase –ex: solutions (all 3 phases) such as air, windex, kool-aid

heterogeneous: see a boundary or regions that look different ex: ice water, granite, suspensions, colloids

Suspensions particles in suspensions are larger than those in solutions components of suspension can be evenly distributed by mechanical means (shaking the contents) but components will settle out

Colloids particles larger than size of molecule but smaller than particles seen with naked eye colloidal dispersion – consists of colloids in a dispersing medium ex: whipped cream, mayonnaise, milk, butter, gelatin, jelly, colored glass

Colloid subtypes

Aerosols: –solid or liquid particles in gas ex: smoke: solid in a gas fog: liquid in a gas

Sols: –solid particles in a liquid ex: milk of magnesia (solid magnesium hydroxide in water)

Emulsions: –liquid particles in liquid ex: mayonnaise (oil in water)

Gels: –liquids in solid ex: gelatin: protein in water quicksand: sand in water

Hints for Mixtures solutions in gas & liquid phases transmit light particles not big enough to scatter light look translucent suspensions look cloudy particles big enough to scatter light settle on standing

CuSO 4 (aq)

Particle Diagrams             atoms of a monatomic element (single same atoms) molecules of a diatomic element (double same atoms)

Particle Diagrams                    molecules of a triatomic compound mixture: - monatomic element - diatomic element - triatomic compound   

Separating Mixtures physically combined separation based on physical properties –sorting: size & appearance –filtration: size solid in liquid –distillation: different bp’s liquids mixed –crystallization: solubility solid in liquid –magnet: magnetization –chromatography: solubility liquids mixed –“travel” ability

suspensions: solid in liquid

liquid goes through filter paper but solid stays behind

Distillation separating liquids with different bp’s mixed together

Paper Chromatograhy separating liquids with different rates of solubility mixed together

Crystallization separating solids from a liquid solution

Conservation of Mass mass begin with = mass end up with # of atoms before = # of atoms after