Classification of Matter PDF

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Classification of Matter 1) Pure Substances - Only one substance is present - Definite and constant composition - Properties are always the same at a given condition - Types: > Elements > Compounds > Elements - is a substance that consists of identical at...

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Classification of Matter

1) Pure Substances - Only one substance is present - Definite and constant composition - Properties are always the same at a given condition - Types: > Elements > Compounds > Elements - is a substance that consists of identical atoms. - cannot be decomposed into other substances. - At this time, 117 elements are known. Of these, 92 occur in nature - has symbols  1st letter or two of their Greek, Latin, English, German - e.g. copper wire, aluminum foil

> Compounds - composed of 2 or more elements in a fixed ratio - properties differ from those of individual elements - e.g. table salt (NaCl) - Compounds a compound of 2 or more different elements bonded together in a fixed proportion. - For example:

- Two different compounds, each has a definite composition. - Slight differences in combinations of atoms can have large difference in properties: > H2O- water, > H2O2 – hydrogen peroxide > C2 H6O – ethanol, drinkable > C2 H6O2 – ethylene glycol, poisonous ELEMENTS  Can be decomposed into simpler substances by chemical changes, always in a definite ration COMPOUNDS  cannot be decomposed into simpler substances by chemical changes

2) Mixtures - are two or more substance that are not chemically combined. - do not have a fixed composition - do not have constant boiling points or melting points - Variable composition - Components retain their characteristic properties - May be separated into pure substances by physical methods - Mixtures of different compositions may have widely different properties. - Variable combination of 2 or more pure substances. > Physical Separation Techniques - Using Bar Magnet  Separate metallic from non-metallic components - Filtration / Decantation  separates solid and liquid - Evaporation  Separates volatile from non-volatile liquids - Distillation  separates two or more liquids with different boiling points

Heterogeneous

Homogeneous

> Homogeneous - 1 phase - Uniform properties - Same composition - Ex. sugar & water >Solution - very small particles - particles don’t settle - very small particles - no Tyndall effect - particles don’t settle - e.g. rubbing alcohol >Heterogeneous - 2 or more phases (with same or different physical states) - each phase has different properties - Ex. oil & water; sand & water > Colloid - medium-sized particles - Tyndall effect - particles don’t settle  > e.g. milk > Suspension - large particles - Tyndall effect

- particles settle  > e.g. fresh-squeezed lemonade

Example

Classification

mayonnaise

colloid

muddy water

suspension

saltwater

solution

Italian salad

suspension

sugar (sucrose)

compound

paint

hetero. mixture

soda

solution

Matter Flowchart...