What is Stoichiometry?

Stiochiometry:
-"Stoichio" comes from Stoichion, the english equivalent is "element"
-""metry" comes from Metron, the english equivalent is "measurement"

Both from the Greek language. Basiccally measuring elements.

Stoichiometry is about measuring the substances within a reaction, this includes the reactant itself and the product. 

When finding the measurements always remember to balance the equation.
CaCO3 -> CaCO + CO2
Identify the ratio = 1:3 By finding the ratio you are now able to do some calculations.