1. Unit 3 Chemical Reactions 3.1 What is a chemical equation? AIM: How can we determine if mass is conserved in a chemical reaction? DO NOW: 1.Why do atoms react with each other? 2.Why does Na react with Cl? In order to achieve a full octet in the valence shell Na wants to become Na +  has an electron configuration of 2-8-1, showing that it wants to lose 1 e - Cl wants to become Cl -  has an electron configuration of 2-8-7, showing that it wasn’t to gain 1 e - Since Na wants to lose and Cl wants to gain an electron, they will ionic bond to form the salt NaCl

2. WHAT IS A CHEMICAL EQUATION? PARTDEFINITION EQUATION CHEMICAL EQUATION REACTANT PRODUCT  right expression has to equal to the left expression Symbolic representation of a chemical reactions where the Reactant side must equal to the product side Substance that enters into a reaction LEFT SIDE Substance that is produced by a reaction RIGHT SIDE Means “yields” Indicates what is produced in the reaction

3. LAW OF CONSERVATION OF MASS The mass of the reactants is equal to the mass of the products This means that mass is neither created nor destroyed in any chemical reaction.

4. NEXT STEPS Complete the Unit 3 Lab 1 If time permits, please complete the question son the back of your worksheet