PHYSICAL & CHEMICAL CHANGE

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"Chemistry is about change." - Kotz


PHYSICAL CHANGE

Definition:  the chemical identity of a substance is preserved even though it may have changed its physical state.

Application: An example of a physical change is the melting of ice producing liquid water.


CHEMICAL CHANGE

Definition:  A change that involves the transformation of one or more substance into one or more different substances.

Application:  The mixture of hydrogen gas and oxygen gas under certain conditions will produce water.

** CHEMICAL EQUATIONS

Definition: A written representation of a chemical reaction, showing the reactants and products, their physical states, and the direction in which the reaction proceeds.


TRY TO ANSWER THE FOLLOWING QUESTION:

* When camping in the mountains, you boil a pot of water on a campfire.  What physical and chemical changes take place in this process??

WHich of these is a Chemical change?

a) The fuel in the campfire burns in air (combustion)

b) The firewood turns the color blue

c) water turns to steam