September 24, 2oo9

A. WHAT MATTERS?

• anything that has mass and occupies space


• matter can exist in many different states, the most common are:
  -solid, liquid, gas
  -plasma, aqueous, amorphous


• SOLIDS: holds one shape and has a definite volume


• LIQUID: can change shape, but has a definite volume


• GAS: can change shape and volume


• AQUEOUS: something dissolved in water


• Solid - strong bonds


• Liquid -weak bonds


• Gas - no bonds


• Plasma - ionization

B. CHANGES IN MATTER:

• matter can undergo any changes


• nearly all changes can be broken down into 3 categories:
  -physical changes, chemical changes, and nuclear changes

PHYSICL CHANGES:

• involves changing shape or state of matter
  -crushing, tearing, ect.


• no newsustances are formed
  -eg. boiling water, cutting wood, smashing cars

PHASE CHANGES

• changing from a solid to a gas can often be confused as a chemical change
  -chemicals remain the same


• during the melting process chemicals usually follow this path:
  

CHEMICAL CHANGE

• new substances are formed
• properties of the matter change
  -conductivity, acidity, color, etc.
  -eg. iron rusting, burning wood, digesting food

C. CONSERVATION OF MATTER

• in physical and chemical changes, matter is neither createrd nor destroyed...EVER. Period.
• this is called the 'conservation of matter'