UNIT ONE – CHAPTER ONEMATTER AND CHANGE

CHEMISTRYCHEMISTRYChemistryThe study of the composition of substances and the changes they undergo.

5 major divisions

1. Organic chemistry: study of all substances that contain carbon.

2. Inorganic chemistry: substances sans carbon.

3. Analytical: composition of substances

4. Physical: concerned with theories and experiments that describe chemicals

5. Biochemistry: study of chemistry of living organisms

LABLABTOOLSTOOLS

OBSERVATIONS & OBSERVATIONS & INFERENCES INFERENCES (INTERPRETATIONS)(INTERPRETATIONS)

OBSERVATION: Making a determination using 1 or more of your 5 senses

Which senses are NOT used in the chemistry lab?

OBSERVATIONS & INFERENCES (INTERPRETATIONS)

INFERENCE/INTERPRETATION: A determination based on prior knowledge (educated guess)

LET’S PRACTICELET’S PRACTICE The sky is really cloudy. A storm is coming. The candle is made of wax. The pan is hot. Ice freezes at 0◦ C Sugar is sweet. The pan is getting ready to boil

over.

MATTERMATTER

Matter: Anything that takes of space and has mass. A golf ball has more matter that a tennis ball.

Mass: The amount of matter an object contains

Substance: a particular kind of matter that has form and definite composition.

Properties of MatterProperties of Matter

Physical Property: a quality or condition of substance that can observed or measured without changing the composition of the substance.

Properties of MatterProperties of MatterPhysical Properties

Extensive: depends on the amount of substance present-example: mass, length, volumeIntensive: independent of the amount of substance present. Examples: color, crystal shape, density, melting and boiling points, ductility, malleability, conductivity.

Chemical PropertiesChemical Properties

Chemical properties-depend on the action of a substance when in the presence of other substances.

Does it:burnHelp others burn?React with H2O ?Is it toxic?What else will it react with?

States of MatterStates of MatterSolid

Has a definite shapeHas a definite volumeParticles are packed closely togetherCannot easily be compressed

States of MatterStates of MatterLiquid

Flows easilyHas a definite volumeIndefinite shape – takes on shape of containerSomewhat tightly packed – not easily compressed

States of MatterStates of MatterGas

Indefinite Shape-Takes on shape of containerIndefinite volume-Takes on volume of containerLots of space between particles- easily compressed

States of MatterStates of Matter

VaporNot the same thing as a gas!Means the gas phase of a substance that is normally a liquid or solid at room temperatureGaseous water is a vaporOxygen is a gas

Changes of MatterChanges of MatterPhysical Changes

Alters a physical property of a substanceComposition of the substance remains the sameExamples:-boiling, freezing, dissolving, breaking crushing, etc.

Changes of MatterChanges of MatterChemical Changes or RxnsAlters the chemical composition of the substanceAfter the change, you do not have the same substance that you started withExamples-burning paper, cooking an egg, etc.

TYPES OF MIXTURESTYPES OF MIXTURES

2 types of mixtures:Homogeneous (solutions) the components that make up the mixture are uniformly distributed throughout the mixture.Salt waterSimple syrupKool-Aid

TYPES OF MIXTURESTYPES OF MIXTURES

Heterogeneous: the components of the mixture are not uniform or have localized regions with different properties.GraniteSandStew

Solvent Solute Example   Medium Dispersed Colloids (fine dispersions)

Suspensions(coarse dispersions)

Gas Gas Air Gas liquid Fog, mist, smoke, hair spray

 

Liquid Gas DO/H2O Gas Solid Aerosols, smoke, cloud, air particulates

 

Solid Solid Bronze (Alloy) Liquid Gas Liquid foam: whipped cream, shaving cream

 

      Liquid Liquid   Emulsion: milk, mayonnaise, hand cream

Liquid Liquid Alcoholic beverages Liquid Solid pigmented ink, blood

mud (soil, clay or silt particles are suspended in water), chalk powder suspended in water

Solid Liquid Salt water Solid Gas Solid foam: aerogel, styrofoam, pumice

Foam: dry sponge

solid Liquid Amalgam(mercuryIn gold or silver)

Solid Liquid Gel: agar, gelatin, silicagel, opal

Wet sponge

      Solid Solid cranberry glass Clay, Silt, Sand, Gravel, Granite

Chemical SymbolsChemical SymbolsMost come from the first letter or two in the name of the elementFirst letter capitalized, following ones are lower caseSome come from the element name in a different language, usually Greek or LatinSome come from the abbreviation of the name of a scientistShorthand way to write the element

Chemical Symbols RulesChemical Symbols Rules

If the symbol consists of letter, it must be an upper case.

If the symbol consists of 2 letters, it must be an upper case with a lower case

Chemical ReactionsChemical ReactionsOne or more substance turn into a new substanceReactants-starting substancesProducts-ending substancesReactants → Products

Reactant + Reactant → Product + Product 

Law of Conservation of Law of Conservation of Mass/MatterMass/MatterStates: In any chemical or physical reaction, mass/matter can neither be created nor destroyed only transferred.

In other words, the mass of the reactants must equal the mass of the products.

MASS VS WEIGHTMASS VS WEIGHT

MASS: The amount of matter an object contains

WEIGHT: the affect that gravity has on a substance.

MASS VS WEIGHTMASS VS WEIGHT

SCIENTIFIC METHODSCIENTIFIC METHOD

1.State the problem

2.Observations

3. Hypothesis

3.Data Gathering/Experiment

4.Conclusion

5. Theory

6.Scientific Law

ACCURACY & PRECISIONACCURACY & PRECISION

Accuracy refers to the closeness of a measured value to a standard or known valuePrecision refers to the closeness of two or more measurements to each other.