Balancing Equations

• By Tyler Dornbusch and Jason Caws

Directions to Game

• Click on a number box• The higher numbers indicate harder questions• Compete with a friend to see who accumulates the

most points• Questions answered incorrectly will cause the

player to lose the number of points indicated in the box

• How To Balance Equations

How To Balance Equations

• Goal: To make all elements in equation equal in numbers of atoms

• To add numbers of atoms to an element, you must add a coefficient to the element. (Ag = 1 atom of silver, 2Ag = 2 atoms of silver)

• Also, you must consider the subscript below the element and multiply it by the coefficient that you add. (2H2 = 4 Hydrogen ions)

How To Balance Equations Continued

• Example 1: H2 + O2 H2O • There are two atoms of hydrogen and two atoms of oxygen

on the reactant (left) side of the equation• Now you must add coefficients to balance both sides of the

equation• 2H2 + O2 2H20• A two is added in front of the Hydrogen atom and the

water molecule to create two oxygen atoms and four hydrogen atoms on both sides of the equation

Another Example

• Al + Cl2 AlCl3

• 2Al + 3Cl2 2AlCl3

• Now we have two aluminum atoms and six chlorine atoms on both sides of the equation

One Last Example

• Fe + H3(PO4) H2 + Fe(PO4)2

• (When parenthesis are added, multiply the subscript that follows the parenthesis with every element inside of the parenthesis)

• Therefore, (PO4)2 has two atoms of Phosphorus and eight ions of Oxygen

• Fe + 2H3(PO4) 3H2 + Fe(PO4)2

• Now there is one atom of Iron, six atoms of Hydrogen, two atoms of Phosphorus, and eight atoms of oxygen on both sides of the equation.

Types of Equations

• Decomposition: One compound decomposes into two atoms– PCl5 PCl3 + Cl2

• Synthesis: Two atoms become an ionic compound– H2 + O2 H2O

Types of Equations Continued

• Single Displacement: One element and one compound react to produce a different element and a different compound– H2 + CuO Cu + H2O

• Double Displacement: Two compounds produce two different compounds– ZnBr2 + AgNO3 Zn(NO3)2 + AgBr

Types of Equations Continued

• Combustion: A hydrocarbon reacts with oxygen to produce carbon dioxide and water– CH4 + O2 CO2 + H2O

Good Luck

• Now enjoy playing Jeopardy and test your knowledge on balancing equations.

• Directions: Click on a number box for a question, and click again to see your answer.– (After each answer, click on the house link to return to

the Jeopardy slide for a new choice of question)

– If you are lucky, you might get some free points for clicking on the mystery question

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Double

Displacement Single

Displacement Synthesis Decomposition Combustion

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• NaCl + Pb(NO3)2 PbCl2 + NaNO3

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• 2NaCl + Pb(NO3)2 PbCl2 + 2NaNO3

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PbCl2 + Li2SO4 LiCl + PbSO4

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PbCl2 + Li2SO4 2LiCl + PbSO4

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FeCl3 + NaOH NaCl + Fe(OH)3

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FeCl3 + 3NaOH 3NaCl + Fe(OH)3

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Na3(PO4) + CaCl2 Ca3(PO4)2 + NaCl

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2Na3(PO4) + 3CaCl2 Ca3(PO4)2 + 6NaCl

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Ba3(PO4)2 + NaClO4 Na3PO4 + Ba(ClO4)2

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Ba3(PO4)2 + 6NaClO4 2Na3PO4 + 3Ba(ClO4)2

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LiI + Cl2 LiCl + I2

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2LiI + Cl2 2LiCl + I2

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S + O2 SO3

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2S + 3O2 2SO3

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AlBr3 + Cl2 AlCl3 + Br2

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2AlBr3 + 3Cl2 2AlCl3 + 3Br2

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Zn + HCl H2 + ZnCl2

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Zn + 2HCl H2 + ZnCl2

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Cl2 + KBr Br2 + KCl

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Cl2 + 2KBr Br2 + 2KCl

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H2 + Br2 HBr

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H2 + Br2 2HBr

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Ag + S Ag2S

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2Ag + S Ag2S

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P4 + O2 P2O5

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P4 + 5O2 2P2O5

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Al + Cl2 AlCl3

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2Al + 3Cl2 2AlCl3

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NH3 + HCl NH4Cl

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NH3 + HCl NH4Cl

This question is already balanced.

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CuO Cu + O2

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2CuO 2Cu + O2

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H2O H2 + O2

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2H2O 2H2 + O2

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Zn(OH)2 ZnO + H2O

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Zn(OH)2 ZnO + H2O

This equation is already balanced.

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Ni(ClO3)2 NiCl2 + O2

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Ni(ClO3)2 NiCl2 + 3O2

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Ag2O Ag +O2

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2Ag2O 4Ag +O2

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CH4 + O2 CO2 + H2O

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CH4 + 2O2 CO2 + 2H2O

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FREE QUESTION:

YOU GET A FREE 200 POINTS

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CONGRATULATIONS!!!!

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C4H10 + O2 CO2 + H2O

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2C4H10 + 13O2 8CO2 + 10H2O

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C6H12O6 + O2 CO2 + H2O

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C6H12O6 + 6O2 6CO2 + 6H2O

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C7H16 + O2 CO2 + H2O

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C7H16 + 11O2 7CO2 + 8H2O