[REVIEW] Physical and Chemical Changes

REVIEW

Physical and Chemical Changes

Poll

Physical changes are __?__ reversible.

• almost never

• usually

Poll

Chemical changes result in new substances.

• True

• False

Poll

Physical changes affect...

• chemical composition (formula)

• appearance only

Chemical Changes

• Almost never reversible.

• Affect chemical composition (the chemical formula).

• A new substance MUST be formed.

Open Ended

List as many clues to (or signs of) chemical change as you can!

Clue #1

Change in Color

Clue #2

Gas released.

Clue #3

Change in temperature.

Clue #4

Change in odor (smell).

Clue #5

Precipitate formed.

The reaction causes a solid (precipitate) to form from a liquid or liquids.