Stoichiometry--By Nemo Jin

Definition:

--ratio between the amount of reactants and the amount of products produced by the reactants in a chemical reaction.

--it is based on the fact that all atoms are conserved in a chemical reaction.

Calculation:

Question: 

How many moles of Cl2 are needed to produce 3.4 moles of NaCl in the chemical reaction which sodium metal and chlorine gas combine to form solid sodium chloride?

Step 1:

Write a balanced equation.

2 Na(s) + Cl2(g) --> 2NaCl(s)

Step 2:

Find the ratio for NaCl to Cl

Cl2/NaCl = 1/2

Step 3:

Convert into NaCl

3.4 moles NaCl x 1 mole of Cl2/2 moles of NaCl = 1.7 moles of Cl2