MixturesMixtures

Matter

Substances Mixtures

Elements CompoundsHeterogeneousMixtures

HomogeneousMixtures

Mixtures Substances separated by physical methodsCompounds Substances separated by chemical methods

MixturesMixtures

•Combo of 2 or more pure substances

•Physically combined NOT chemically combined

•Each substance retains its own identity and properties

MixturesMixtures• Variable composition

• No unique properties

• Ex: sugar and sand mixed together

• Separated by physical methodsphysical methods

• May be homogeneous or heterogeneous

TypesTypes of Mixtures of Mixtures• Heterogeneous: See boundary or

regions that look different

Ex:

•colloids •suspensions•ice water•granite•cereals

Colloid: milk

Suspension: smoke/smog

Heterogeneous mixture: ice water

Heterogeneous mixtures: cereal/granite

• Homogeneous: constant composition throughout, single phase

Ex:

•Solutions (all 3 phases)•Air•Windex•kool-aid

Air

Homogeneous Solutions:

Drink mixWindow cleaner

Hints for MixturesHints for Mixtures• Solutions (gas & liquid phases) transmit

light • No particles big enough to scatter light • Look translucent (see-through)

• Suspensions look cloudy – scatter light• Particles big enough to scatter light• Settle upon standing

Where does this liquid fit?

Homogeneous?

Heterogeneous?

Particle Diagrams

Atoms only: monatomic element

Molecules:diatomic element

Particle Diagrams

Molecules: •triatomic compound

Mixture: •monatomic element•diatomic element•triatomic compound

Conservation of MassConservation of Mass

•Mass before = Mass after•# atoms before = # atoms

after

Separating MixturesSeparating Mixtures• Physically combined• Separation based on physical properties

– Sorting: Appearance– Filtration: Size– Distillation: Boiling Point– Crystallization: Solubility– Magnet: Magnetization– Chromatography: “Travel” ability

Filter:

Solid particles can be separated from liquid

DistillationUsed to separate liquids with different boiling points

Paper Chromatograhy

Can separate liquids with different solubilities

Crystallization

Can separate solids dissolved in liquids