Alchemists developed the tools and techniques for working with chemicals.
Lavoisier helped to transform chemistry from a science of observation to the science of measurement that it is today.
Scientific method
Observations
Hypotheses
Experiments scientific law
Theory
Extensive
Depends on the amount of matter in a sample
Mass
Volume
Heat capacity
Intensive
Depends on the type of matter
Density
pH
Color
Boiling/freezing point
Half-life
Physical
Quality or condition of a substance that can be observed or measured without changing the substances composition.
Color
Boiling point
Melting point
Hardness
Odor
Solubility
Taste
States of matter
Solid
Def shape, def volume, not compressible
Liquid
Indef shape, def volume, not compressible
Gas
Indef shape, indef volume, compressible
Plasma – does not occur naturally on earth.
Mixtures
Homogeneous (solution)
1 phase salt/sugar water air Heterogeneous
Mixture where the composition is NOT uniform throughout.
Element
Simplest form of matter
Compound
Formed from 2 or more atoms.
Most contain 2 or more elements.
Can be broken down into simpler substances.
Symbols
Represent elements
Formulas
Represent compounds
Chemical changes
The composition of matter always changes
Burn
Rot
Decomposes
Indications of a chemical reaction
Transfer of energy
Change in color
Production of gas
Formation of a precipitate
Conservation of mass
During any chemical reaction, the mass of the product is always equal to the mass of the reactants.
Mass is neither created nor destroyed.
In any physical change or chemical reaction, mass is conserved.
Accuracy