1. Standard 5a: Chemical reactions change the molecules Subscripts and coefficients 23

2. Standard 5a: Chemical reactions change the molecules Standard 5b conservation of matter Balancing Equations 24 In any reaction mass is not __________ or __________, but __________. This is called ________________________________________ That means that the __________ number of elements must be present on __________ of a chemical __________. In a __________ __________ the number of __________ must equal the __________. You can write out any chemical equation in __________ or using __________ __________. Let’s look at our baking soda vinegar balloon experiment: In words the reaction looks like: __________ __________ (Baking soda) __________ __________ (Vinegar) produces __________ __________ + __________ + __________ __________ Using chemical symbols it looks like: NaHCO 3 + HC 2 H 3 O 2 → NaC 2 H 3 O 2 + H 2 O + CO 2 If the __________ = the __________ then the equation is __________ In any reaction mass is not __________ or __________, but __________. This is called ________________________________________ That means that the __________ number of elements must be present on __________ of a chemical __________. In a __________ __________ the number of __________ must equal the __________. You can write out any chemical equation in __________ or using __________ __________. Let’s look at our baking soda vinegar balloon experiment: In words the reaction looks like: __________ __________ (Baking soda) __________ __________ (Vinegar) produces __________ __________ + __________ + __________ __________ Using chemical symbols it looks like: NaHCO 3 + HC 2 H 3 O 2 → NaC 2 H 3 O 2 + H 2 O + CO 2 If the __________ = the __________ then the equation is __________ Na: H: C: O: Na: H: C: O: I can balance chemical equations! Compounds on the left of the arrow are called ___________ Compounds on the right of the arrow are called __________ The arrow means ______________ Balance the following equations: 4 Mg + O 2  MgO 5 HgO  Hg + O 2 6 Na + Br 2  NaBr 7 C + H 2  CH 4 8 Cl 2 + NaBr  NaCl + Br 2 I can balance chemical equations! Compounds on the left of the arrow are called ___________ Compounds on the right of the arrow are called __________ The arrow means ______________ Balance the following equations: 4 Mg + O 2  MgO 5 HgO  Hg + O 2 6 Na + Br 2  NaBr 7 C + H 2  CH 4 8 Cl 2 + NaBr  NaCl + Br 2 Glue your balancing equations worksheet on the output  And the notes on the input 

3. In any reaction mass is not __________ or __________, but __________. This is called ________________________________________ That means that the __________ number of elements must be present on __________ of a chemical __________. In a __________ __________ the number of __________ must equal the __________. You can write out any chemical equation in __________ or using __________ __________. Let’s look at our baking soda vinegar balloon experiment: In words the reaction looks like: __________ __________ (Baking soda) __________ __________ (Vinegar) produces __________ __________ + __________ + __________ __________ Using chemical symbols it looks like: NaHCO 3 + HC 2 H 3 O 2 → NaC 2 H 3 O 2 + H 2 O + CO 2 If the __________ = the __________ then the equation is __________ In any reaction mass is not __________ or __________, but __________. This is called ________________________________________ That means that the __________ number of elements must be present on __________ of a chemical __________. In a __________ __________ the number of __________ must equal the __________. You can write out any chemical equation in __________ or using __________ __________. Let’s look at our baking soda vinegar balloon experiment: In words the reaction looks like: __________ __________ (Baking soda) __________ __________ (Vinegar) produces __________ __________ + __________ + __________ __________ Using chemical symbols it looks like: NaHCO 3 + HC 2 H 3 O 2 → NaC 2 H 3 O 2 + H 2 O + CO 2 If the __________ = the __________ then the equation is __________ created destroyed transferred The law of conservation of mass same Each sideequation Chemical reaction reactants products words chemical symbols sodiumbicarbonateAceticacid Carbon dioxide waterSodium acetate Na: H: C: O: Na: H: C: O: reactantsproductsbalanced

4. Did you get them correct? Mg + O 2  MgO Na + Br 2  NaBr C + H 2  CH 4 Cl 2 + NaBr  NaCl + Br 2 2 2 2 2 2 22