Warm- Up Describe a simple demonstration you could do to show a chemical reaction has taken place. What can you do to change the rate of this reaction. Have HW Out

Law of Conservation of Matter Chapter 3.2D NCSCOS 4.06 and 4.07

Chemical Reactions Review REACTANTS  PRODUCTS Baking Soda + Vinegar  PRODUCTS Question: In this reaction, do you think the mass will change?

Reactants = Products The Law of Conservation of Matter states that the mass of the reactants and products will ALWAYS be the SAME! Matter can not be created or destroyed!!

The Law of Conservation of Matter Conservation of Mass The mass of products will be the same as the mass of the reactants… The easiest way to do this is to count the total number of each atom on each side of the reaction. Ex: C + O2  CO2

Equations must be Balanced This is the tricky part… Iron + Oxygen  Iron Oxide (Rust) Fe + O2 Fe2O3 What type of reaction is this?

Balancing Equations Important Rules: SUBSCRIPTS CAN NEVER BE CHANGED Chemical Formulas can not be changed. The only change that may occur is to the COEFFICIENT in front of each formula

What type of reaction is this? Balancing HgO→Hg + O2 Can you balance this? What type of reaction is this?

Balancing Balance this equation: NH3  N2 + H2 What type of reaction is this?

Assignment and Homework Complete the small worksheet and attach in your notebook. (Informal assessment grade!) Review all chemistry notes taken so far.