1. Balancing Chemical Equations
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2. Components of chemical equations
Starting materials – reactants
Conditions of reactants – state
Proportions of reactants – coefficients
Instructions for reacting – ‘+’ sign
Resulting product – products
Proportions of products - coefficients

3. The Balancing Act Step 1: Write the word equation
Magnesium + oxygen magnesium oxide
Step 2: Write the skeleton equation
Mg(s) + O2(g) MgO(s)
Step 3: Count the # and kinds of atoms
Mg(s) + O2(g) MgO(s)
1 Mg atoms Mg atom
2 O atoms O atom

4. The Balancing Act Step 4: Write coefficients to balance
2Mg(s) + O2(g) MgO(s)
2 Mg atoms Mg atoms
2 O atoms O atoms

5. The Balancing Act Step 1: methane + oxygen carbon dioxide + water
Step 2: CH4(g) + O2(g) CO2(g) + H2O(l)
Step 3: 1 C atom C atom
4 H atoms H atoms
2 O atoms O atoms
Step 4: CH4(g) + 2O2(g) CO2(g) + 2H2O(l)

6. The Balancing Act Step 1: zinc (s) + silver nitrate (aq)
zinc nitrate (aq) + silver (s)
Step 2: Zn (s) + AgNO3 (aq) Zn(NO3)2 + Ag (s)
Step 3: 1 Zn 1 Zn atom
1 Ag 1 Ag atom
1 NO3 2 NO3
Zn(s) + 2AgNO3 (aq) Zn(NO3)2 (aq) + 2Ag (s)

7. Try This:
Write a balanced equation for the reaction between iron (III) nitrate and sodium hydroxide to produce iron (III) hydroxide and sodium nitrate.

8. Skeleton equation: Fe(NO3)3 + NaOH Fe(OH)3 + NaNO3 1 Fe atom 1 Fe atom
3 NO3 ion NO3 ion
1 Na atom Na atom
1 OH ion OH ions

9. Balanced Equation Fe(NO3)3 + 3NaOH Fe(OH)3 + 3NaNO3
1 Fe atom Fe atom
3 NO3 ions NO3 ions
3 Na atoms Na atoms
3 OH ions OH ions

10. Steps to balancing chemical equations
- Balance the # of atoms simply by adding a coefficient in front of the chemical formula containing the element or compound you are trying to balance
1. Balance all other atoms except hydrogen and oxygen first
2. Balance oxygen
3. Balance hydrogen
4. Check – to ensure that all the atoms are now balanced

11. Rules to Remember: Do: write proper formulas in skeleton equations
Do: double-check that balancing one element doesn't unbalance another
Never
Ever
Not even once
Change the subscripts!

12. (iodine) Zn (uranium) have the (boron)(lutetium)(einsteinium)
(iodine) Zn (uranium) have the (boron)(lutetium)(einsteinium). These (tungsten)ill Cm!
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