Unit 1 Intro to Chemistry and Measurement

Unit 2Matter and ChangeChemistry IMr. PatelSWHS

Topic OutlineContinue to Learn Major Elements and SymbolsProperties of Matter (2,1, 2,2, 2,3)Physical and Chemical Changes (2.1, 2.4)Inter-/Intra-molecular ForcesStates of Matter (13.2, 13.2, 13.3) Kinetics/KMT, Phase Change (13.1, 13.4)Properties of MatterRemember matter is anything that has mass and occupies volume.

Matter is described using properties that are extensive or intensive properties.

Extensive PropertiesExtensive Property a property that depends on the amount of matter in a sample. (Changes with amount)Mass measure of the amount of matter an object contains

Volume measure of the space taken up

Other examples: energy, weight, length, areaIntensive PropertiesIntensive Property a property that does NOT depend on the amount of matter

Density D = mass/volume matter per unit volume

Other examples: hardness, melting/freezing point, concentration, viscosity

Classify the statement as Intensive or ExtensiveThe Boiling point of water is 100OC.

The mass if 300 kg.

The length is 30 m.

The density of water is 1.0 g/mL.Intensive

Extensive

Extensive

Intensive

SubstanceAll matter can be divided into substances and mixtures

Substance uniform and definite composition

Every sample of a substance has identical intensive properties. Why?Copper Kettle

Gold SculptureMatterAnything that has mass and volumeSubstanceConstant Composition; All particles identicalEx: Water, HeliumMixtureVariable Composition; 2 or more substancesEx: Sand, SoilPhysicallySeparateSubstancesSubstances can be classified as elements or compounds

Element simplest form of matter with unique set of properties (all atoms same)Ex: Gold, Hydrogen, Oxygen (on periodic table)

Compound two or more elements chemically combined in fixed ratiosEx: Water, salt, baking soda

Compounds can be chemically separated to elements

MatterAnything that has mass and volumeSubstanceConstant Composition; All particles identicalEx: Water, HeliumMixtureVariable Composition; 2 or more substancesEx: Sand, SoilElementMade up of identical atoms; on Periodic TableEx: Zinc, UraniumCompoundMade up of 2 or more elements; combined chemicallyEx: Carbon dioxidePhysicallySeparateSeparateChemicallyMixturesMixture a physical blend of two or more components (substances)

Heterogeneous Mixture the composition is not uniform throughoutEx: soil, chicken noodle soup

Homogeneous Mixture (solution) composition is uniform throughoutEx: salt water, alloys (solid in solid)MixturesMixtures can be separated physically

Filtration solid from liquid

Distillation liquid from liquid or solid

Steel = Iron + Carbon

MatterAnything that has mass and volumeSubstanceConstant Composition; All particles identicalEx: Water, HeliumMixtureVariable Composition; 2 or more substancesEx: Sand, SoilElementMade up of identical atoms; on Periodic TableEx: Zinc, UraniumCompoundMade up of 2 or more elements; combined chemicallyEx: Carbon dioxidePhysicallySeparateSeparateChemicallyHeterogeneousUneven Distribution; easy to separateEx: Vegetable SoupHomogenousUniform Distribution; called solutionEx: Tap water, SteelPhysical Changes and PropertiesPhysical Property measured properties that do not change the nature of the sampleEx: Boiling Point, Density, Mass

Physical Change some properties may change but the composition of the material does not changeEx: Boiling, Freezing, Cutting, SplittingCan be Reversible or Irreversible

Physical Changes and PropertiesPhysical Changes do not involve chemical reactionsNo Breaking or Forming Chemical BondsSubstance is the same before and after the changeChemical Changes & PropertiesChemical Property the ability of a substance to undergo a chemical reactionEx: Flammability, Combustibility, decomposition

Chemical Change the composition of matter will always changeEx: Burning, exploding, reacting, rusting, rottingAlso called a chemical reaction

Signs of Chemical ChangesClues for a chemical reaction:Transfer of Energy heat, sound, lightColor ChangeGas ProductionFormation of Precipitate solid that settles out of a liquid mixture

Dont confuse for a physical change

Conservation of MassLaw of Conservation of Mass mass is neither created nor destroyed; it is only transformed.

The mass before a reaction must always equal the mass after a reaction

Classify: Physical or Chemical ChangeBurning GasolineEvaporation of WaterStripping a Copper WireMold Growing on YogurtAlka-Setlzer tabletsChemicalPhysical

Physical

Chemical

Chemical

Molecular ForcesINterMolecular ForcesIntramolecular forcesForces between individual molecules

Strong by Numbers

Ex: Hydrogen Bonding, Dipole forces, Dispersion Forces

Contribute to Physical ChangesForces within a specific, individual molecule

Very Strong

Ex: Ionic Bond, Covalent Bond, Metallic Bond

Contribute to Chemical Changes