Chemical Equations

A chemical equation is like a math problem, but a little different.  Chemical equations show what happens when you put different substances together and shows what new substances are formed.
On the left side of the equation, is the reactants.  These are the substances that REACT together.  You put a + sign to separate the substances. Then, you put an arrow to the right.  The arrow means "yields" or "produces."
On the right side of the equation, is what is produced from this reaction or the Products. You also put a + sign to separate the products.
By knowing the reactants, you can predict the products.  From the law of conservation of energy, all of the elements that are represented on the reactant's side, will end up on the product's side, but rearranged to make new substances.
See the example below:

4 Hydrogens and 2 Oxygens -----> 4 hydrogens and 2 Oxygens


Another Example:

Ca(OH)₂ + CO₂ à CaCOз + H₂O

1 Calcium, 4 Oxygens, 2 Hydrogens ---> 1 Calcium, 4 Oxygens, 2 Hydrogens

Same amount on each side - no elements are added and no elements are taken away