Classification of MatterClassification of Matter

Matter

1. Pure Substance 2. Mixtures

a. Element b. Compound a. Homogeneous b. Heterogeneous

Combine to form

Bond to form

Composition is always the same, Composition is always the same, where ever it comes from (pure gold)where ever it comes from (pure gold)

Composition means what it is made of Composition means what it is made of

a. Element – a. Element – Simplest form of matterSimplest form of matter Made up of identical atoms Made up of identical atoms Cannot be broken downCannot be broken down

B. Classification of MatterB. Classification of Matter1. Elements1. Elements

http://periodic.lanl.gov/default.htm

b. Compoundsb. Compounds More than 1 kind of element joined More than 1 kind of element joined

by bonds (COby bonds (CO22, , NaCl)) Can only be separated by chemical Can only be separated by chemical

reactions reactions Represented with a chemical Represented with a chemical

formulaformula Letters indicate type of element Letters indicate type of element Subscripts tell how manySubscripts tell how many

CaCOCaCO33

1 calcium atom3 oxygen atoms

1 carbon atom

Chemical Formulas:Chemical Formulas:

5 atoms total

* Molecule* Moleculemore than 1 atom held by more than 1 atom held by covalent bonds (all elements in covalent bonds (all elements in a molecule are nonmetals)a molecule are nonmetals)

2. Mixtures2. Mixtures Combination of 2 or more pure Combination of 2 or more pure

substancessubstances Composition of mixtures varies from Composition of mixtures varies from

source to sourcesource to source Components can be separated by physical Components can be separated by physical

means (magnet, filter, distillation)means (magnet, filter, distillation) NO chemical formulaNO chemical formula List of ‘ingredients’List of ‘ingredients’

a. Homogenous mixturesa. Homogenous mixtures Is the same thing throughout Is the same thing throughout

one sampleone sample Also known as solutionsAlso known as solutions Like tap waterLike tap water

Blood is not homogeneous because it has different cells…so sometimes you need additional information

b. Heterogenous Mixtureb. Heterogenous Mixture Composition varies within one Composition varies within one

samplesample

AluminumAluminum Unlined PaperUnlined Paper GoldGold Orange juice with pulpOrange juice with pulp Fruit on the bottom yogurtFruit on the bottom yogurt Black coffeeBlack coffee DiamondDiamond Buckminsterfullerene (CBuckminsterfullerene (C6060)) Clean AirClean Air Octane (COctane (C88HH1818)) GlucoseGlucose Oil and waterOil and water

c.c. Separation – physical ways to Separation – physical ways to separate mixtures (chemical separate mixtures (chemical reactions separate elements in a reactions separate elements in a compound)compound)

- elements cannot be broken down further and still keep their properties

- Some are stable and can be found by themselves in nature. Others are so unstable, they will only be found combined with other elements.

- about 100 different elements

- identified by 1 or 2 letter symbols. Letters often are the first letters of the name of the element (Chlorine -> Cl)

- organized in a specific way into the Periodic Table of Elements

Elements

• Element- a pure substance consisting of a single type of atom

Metals_: properties include malleability, ductility, good conductors of heat/electricity, magnetic

Nonmetals_: properties include poor conductors of heat & electricity, solids are brittle & dull

_Metalloids__: have both characteristics of metals and metalloids

Periodic Table of the Elements

The Periodic Table organizes elements into a set of patterns, arranged by increasing atomic number, invented by Russian chemist Dimitri Mendelev (1869)

http://periodic.lanl.gov/downloads.shtml

• Metals: Sodium (Na), Iron (Fe), and Aluminum (Al)

- Shininess, magnetic- malleability: ability of a substance to be molded/formed- conductivity: ability of a substance to transfer

heat/electricity

• Reactivity: willingness and ability to combine with other elements

- Many of the elements are so reactive that they are not

found alone in nature. Wanna see how reactive?

- brittle, dull, not magnetic, not malleable- have poor conductivity - good insulators- many are gases, tend to be reactive

• Nonmetals: Hydrogen (H2), Oxygen (O2), Carbon (C), Chlorine (Cl)

Properties of Elements