The Law of Conservation of Mass states that mass cannot be created or destroyed, only transferred. 

In this lesson you are refreshing your knowledge about how to count atoms in a chemical formula unit. Then you are expanding what you know by learning how to count atoms in chemical formula units with coefficients and parenthesis.  The goal of this is to be able to determine if a chemical formula is balanced or unbalanced. If a chemical formula has the same number and type of atoms on both sides of the arrow, we call this balanced

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INSTRUCTIONS: We took Focus Notes in class, but you can use the following video to take notes. It gives step by step instructions you can use to complete the practice problems worksheet. 

Essential Question: How can you tell if a chemical formula follows the Law of Conservation of Mass? 

Video: https://www.youtube.com/watch?v=CvGoR26vZK8&t=319s