Middle School
Chemical
Reactions
And Mass Balance
Explore
What do these all have in common?
Iron rods in copper sulphate, a single displacement reaction, copper is precipitated
Explosion, combustion reaction
Copper in nitric acid creating nitrogen dioxide gas
Explore
What do these all have in common?
They are all Chemical Reactions!
…but what is a chemical reaction?
Explanation
Chemical Reaction: Atoms rearrange themselves to form a new substances.
Atoms are the building
blocks of everything!
Example
Atoms
Example
The number of and are the same on both sides. Only the order is rearranged.
Mass “stuff” is always conserved
The amount of STUFF before the reaction and after the reaction is always the same
O2
Mass “stuff” is always conserved
The amount of STUFF before the reaction and after the reaction is always the same
gases
=
Conservation of Mass
O2
Signs of Chemical Reaction
Creating solid, liquid, or gas:
Elephant’s toothpaste
Hydrogen peroxide degradation in soap using a iodine catalyst
Baking soda and vinegar
Signs of Chemical Reaction
Color change:
Fire:
Heated Potassium Chlorate Reacts with a Gummi Bear
Iodine clock reaction
Other examples of chemical reactions
Experiment
Test the Law of Conservation of Mass
Identify the signs of a chemical reaction