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Balancing Chemical Equations
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Warm Up What is a chemical reaction?
What are the reactants? What are the products? EQ: How do we balance chemical equations? HOT Q1: What is a chemical reaction? HOT Q2: What does the law of conservation of mass state? HOT Q3: What are the steps for balancing chemical equations?
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Agenda Warm Up/Objective How ‘Bout Them Apples Chemical Reaction Notes
Chemical Reaction Practice Worksheet 7.2 Exit Ticket
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Chemical Reaction Notes
- a process that leads to the transformation of one set of chemical substances to another
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Chemical Reaction Notes
2. Two Sides of the Chemical Equation Reactants – Products – ___Li + ___Br2 ___ LiBr Reactants Products
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What’s up with the apples?
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How ‘Bout Them Apples
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Chemical Reactions Br Br Br Br Li Li Li Li
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For the rest of today, we will be balancing chemical equations.
This will seem like a bunch of rules a chemist made up unless you understand the following concepts.
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Chemical Reaction Notes
1. Law of Conservation of Mass 2. Chemical reactions MUST BE BALANCED The number of atoms on the reactant side and the product side must be EQUAL But how do we count the number of atoms?
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Counting Atoms Rules 3P6Cl3
1. Subscripts apply to the element immediately before it Ex) MgCl2 #Mg ____ #Cl_____ 2. Coefficients multiply the entire molecule Ex) 2C6H2 #C___ #H____
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3. If there are parentheses, the subscript multiples everything inside the parentheses
Ex) 3Be(NO3)2 #Be___ #N____ #O____
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Counting Atoms 1. H2SO4 2. Ca(OH)2 3. NaCl 4. (NH3)3PO4 5. 3H2O
How many atoms of each element are in the following molecules? 1. H2SO4 2. Ca(OH)2 3. NaCl 4. (NH3)3PO4 5. 3H2O
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To decide if an equation is balanced, compare the number of atoms of each element that appear on each side of the equation. If the number of atoms is equal then the equation is balanced, if not equal than the equation is not balanced Ex) N2 + 3 H2 2 NH3 Is it balanced?
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You Try! C3H8 + 5 O2 3 CO2 + 4 H2O Is is balanced?
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Ok, cool. BUT HOW DO WE BALANCE THESE BAD BOYS????!!!
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When balancing… Step 1: Draw a line between products and reactants
Step 2: Tally up atoms of each element on each side Step 3: Change coefficients to start balancing (never change subscripts!) Step 4: Recalibrate each time you change a coefficient Step 5: CHECK YOUR WORK!
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Balancing Chemical Reactions
Notes Balancing Chemical Reactions Ex 1: ____N2 + ____H2 ___NH3
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Balancing Chemical Reactions
Notes Balancing Chemical Reactions Ex 2: ____FeO ____Fe ____O2
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The best way to learn this is to practice.
With a partner, balance the following equations: ____NO + ____O2 ___NO2 ____H2 + ____Cl2 ___HCl ____Fe + ____Cl2 ___FeCl3 4. ____CH4 + ____O2 ___CO2 + ___H2O
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Partner Practice 1. ____NO + ____O2 ___NO2
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Partner Practice 2. ____H2 + ____Cl2 ___HCl
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Partner Practice 3. ____Fe + ____Cl2 ___FeCl3
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Partner Practice 4. ____CH4 + ____O2 ___CO2 + ___H2O
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Partner Practice 5. ____ K + ____ Cl2 ____ KCl
6. ____ N2 + ____ F2 ____ NF3
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Independent Practice For the rest of class, work on (and complete, if possible) Worksheet 6.1 If you get done: come and see me. If you are done, I will have you check your answers against my answer key. If you get any wrong, you must go back and fix them. If you get done with that: You may help a neighbor for beast mode status.
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Exit Ticket Balance the following equations: ___Na + ___Cl2 ___NaCl
___Al + ___HBr ___AlBr3 + ___H2
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___GaF3 + ___ Cs ___ CsF + ___ Ga
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___ CF4 + ___Br2 ___CBr4 + ___F2
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___SeCl6 + ___O2 ___SeO2 + ___Cl2
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