1. What is the law of conservation of mass? 2. How is the law of conservation of mass related to balancing equations?

3. What is a balanced chemical equation?

4. Balance the following combustion reaction, and draw a corresponding picture of the correct number of
particles.

C2​H4​ + O2​ → CO2​ + H2​O

5. I have ten moles of iron atoms in the reactant side of a reaction. Do I have enough information to determine
how many moles of iron atoms I will have following the reaction? If so, how many moles of iron atoms will I
have at the end of a reaction? If not, what else do I need to know?

6. I have three moles of Methane (CH4​) on the reactant side of the reaction. Do I have enough information to
determine how many moles of products I will have following a reaction? If not, what else do I need to know?