Chemical and Physical Changes 9 Science

Definitions  Chemical Change- A change where new particles are formed and are usually not reversible  Physical Change- a change which does not alter the identity of the sample ( no new substance is formed) and the change can be reversed.

Observations (things you can expect to see which accompany a chemical change)  Bubbles  New color  Heat or light given off  Precipitate forms  * new substance forms  *it’s not reversible

Observations for a Physical Change  No new substance formed  Can be reversed

Chemical/Physical Property  Chemical Property- any property which describes how a substance reacts with another substance  Physical Property- a property which can be observed/ measured without forming a new substance  ** these can be either Qualitative or Quantitative

Qualitative  Describes but not measured  Size  Color  Taste  Smell  Texture  Ductile (stretch)  Malleable (flattened, shaped)

Quantitative  Can be measured  Melting point  Boiling point  Density, etc.

Terms:  Solute- substance which is dissolved ( in the smallest amount)  Solvent- the substance that does the dissolving ( in the largest amount)  Define- element and compound

Make 2 headings (Chemical and Physical) and place the following words under the appropriate heading:  Respiration* cooking meat* eroding soil  Freezing* ice melting* iron rusting  Burning paper* steaming rice* evaporating  Wearing down an eraser* grinding wheat* frying bacon  Wood rotting* building a snowman*chopping logs  Bending iron* slicing a cake*etching glass with acid to  Fireworks* breaking glassmake stained glass  Burning logs* car burning gas  Baking a cake* digesting dinner  Condensing* drying hair