Stoichiometry is all about the amount of substances that are involved in a chemical reaction. You can use stoichiometry to find the amount of a substance before a reaction, or even how much of a material that is produced after the reaction.
Reactions are dependent on the amount of product you have. So stoichiometry can help you figure out how much of a compound you will need, or how much you should start off with.
Almost all of there equations can be solved in 4 steps, and at first it may seen hard, but after practice it becomes easier.
1.Balance the equation.
2. Convert units of a given substance to moles.
3. Using the mole ratio, calculate the moles of substance yielded by the reaction.
4. Convert moles of wanted substance to desired units.