Balancing Chemical Equations

Can’t Create or Lose Atoms

A B

A B A B

2A + 2B ABNot Balanced

You must have the same number of each type of atom on each side of an equation.

Balancing Chemical Equations

Can’t Create or Lose Atoms

A B

A B

A B

2A + 2B 2ABBalanced

You must have the same number of each type of atom on each side of an equation.

A B

FORMATION OF WATER

You must have the same number of each type of atom on each side of an equation.

Hydrogen and Oxygen Combine to form water. Write and Balance this equation.

FORMATION OF WATER

H2 + O H20

You must have the same number of each type of atom on each side of an equation.

Hydrogen and Oxygen Combine to form water. Write and Balance this equation.

FORMATION OF WATER

H2 + O H20

H O

HH

O

You must have the same number of each type of atom on each side of an equation.

H

+

Hydrogen and Oxygen Combine to form water. Write and Balance this equation.

HYDROGEN AND OXYGEN ARE DIATOMIC

H2 + O2 H20

HO

HH

O

H

+

Have No Fear Of Ice Cold Beer

O

HYDROGEN AND OXYGEN ARE DIATOMIC

H2 + O2 H20

HO

HH

O

H

+

Have No Fear Of Ice Cold Beer

O

LEFT RIGHTH O H O

HYDROGEN AND OXYGEN ARE DIATOMIC

H2 + O2 H20

HO

HH

O

H

+

Have No Fear Of Ice Cold Beer

O

LEFT RIGHTH O H O2 2 2 1

You have to balance equations by changing Coefficients!

HYDROGEN AND OXYGEN ARE DIATOMIC

H2 + O2 2H20

Have No Fear Of Ice Cold Beer

LEFT RIGHTH O H O2 2 2 1

You have to balance equations by changing Coefficients!

H O

HH

O

H+O

H

O

H

HYDROGEN AND OXYGEN ARE DIATOMIC

H2 + O2 2H20

Have No Fear Of Ice Cold Beer

LEFT RIGHTH O H O2 2 2 1

2 2 4 2 You have to balance equations by changing Coefficients!

H O

HH

O

H+O

H

O

H

HYDROGEN AND OXYGEN ARE DIATOMIC

2H2 + O2 2H20

Have No Fear Of Ice Cold Beer

LEFT RIGHTH O H O2 2 2 1

2 2 4 2 You have to balance equations by changing Coefficients!

H O

HH

O

H+O

H

O

H

HYDROGEN AND OXYGEN ARE DIATOMIC

2H2 + O2 2H20

Have No Fear Of Ice Cold Beer

LEFT RIGHTH O H O2 2 2 1

2 2 4 2

4 2 4 2

You have to balance equations by changing Coefficients!

H O

H H

O

H

+O H

O

H

H

H

Ethylene and Oxygen form Carbon Dioxide and Water

C2H4 + O2 CO2 + H20LEFT RIGHT

C H O C H OFirst we need to count atoms!

Ethylene and Oxygen form Carbon Dioxide and Water

C2H4 + O2 CO2 + H20LEFT RIGHT

C H O C H O2 4 2 1 2 3

First we need to count atoms!

HO

CO

H

H H

C CHH

OO

O

Ethylene and Oxygen form Carbon Dioxide and Water

C2H4 + O2 2CO2 + H20LEFT RIGHT

C H O C H O2 4 2 1 2 3

2 4 2 2 2 5

First we need to count atoms!

HO

CO

H

H H

C CHH

OO

OC

O

O

Ethylene Oxygen form Carbon Dioxide and Water

C2H4 + O2 2CO2 + 2H20LEFT RIGHT

C H O C H O2 4 2 1 2 3

2 4 2 2 2 5

First we need to count atoms!

HO

CO

H

H H

C CHH

OO

OC

O

O

Ethylene and Oxygen form Carbon Dioxide and Water

C2H4 + O2 2CO2 + 2H20LEFT RIGHT

C H O C H O2 4 2 1 2 3

2 4 2 2 2 5

2 4 2 2 4 6

First we need to count atoms!

HO

CO

H

H H

C CHH

OO

OC

O

O

HH

O

Ethylene and Oxygen form Carbon Dioxide and Water

C2H4 + 3O2 2CO2 + 2H20LEFT RIGHT

C H O C H O2 4 2 1 2 3

2 4 2 2 2 5

2 4 2 6 2 4 6

First we need to count atoms!

H O

C O

H

H H

C

C HH

OO

O

C

O

O

HH

O

O

O

O

O

Assignment

Reactants = Products#Atoms of each element on Left = #Atoms of each element on Right

Change ONLY the Coefficients (NEVER change subscripts!)Use a table or draw a picture if it helps. I recommend a grid or table.

Remember: Have No Fear Of Ice Cold Beer

LEFT RIGHTE L E M E N T S

Phet Physics:Balancing Chemical Equations

Run in (HTML5)Introduction: 3 problems…

1) Make Ammonia N2 + H2 NH3 2) Separate Water H2O H2 + 02 3) Combust Methane CH4 + O2 H2O +CO 2

Skeleton Equations to Balance

• Ca + O2 CaO

• N2 + H2 NH3

• Fe + O2 Fe2O3

• Cu2O + C Cu + CO2

• H2O2 H2O + O2

Sample Equations to Balance

• Ca + O2 CaO

• N2 + H2 NH3

• Fe + O2 Fe2O3

• Cu2O + C Cu + CO2

• H2O2 H2O + O2

• 2Ca + O2 2CaO

• N2 + 3H2 2NH3

• 4Fe + 3O2 2Fe22O3

• 2Cu2O + C 4Cu + CO2

• 2H2O2 2H2O + O2

Balancing Act Write and Balance the following equations.

• Hydrogen and Oxygen react to form water.

• Calcium hydroxide and sulfuric acid react to produce calcium sulfate and water.

• Aluminum and Oxygen combine to form Aluminum Oxide.

• Hydrochloric acid and solid sodium hydrogen carbonate form aqueous sodium chloride, water and carbon dioxide.

• Phosphoric Acid + Sodium Hydroxide yield sodium phosphate and water

• Hydrochloric Acid : HCl• Sulfuric Acid H2SO4

• Phosphoric Acid:H3PO4

Balancing Act Write and Balance the following equations.

• Hydrogen and Oxygen react to form water.

• Calcium hydroxide + sulfuric acid react to produce calcium sulfate and water.

• Aluminum and Oxygen combine to form Aluminum Oxide.

• Hydrochloric acid and solid sodium hydrogen carbonate form aqueous sodium chloride, water and carbon dioxide.

• Phosphoric Acid + Sodium Hydroxide yield sodium phosphate and water

• H2 + O2 H20

• 2H2 + O2 2H20

• Ca(OH)2 + H2SO4 CaSO4 + H20

• Ca(OH)2 + H2SO4 CaSO4 +2H20

• Al + 02 Al2O3

• 4Al + 302 2Al2O3

• HCl (aq) + NaHCO3 (s) NaCl (aq) + CO2 (g) + H20 (l)

• Already Balanced

• H3PO4 + NaOH Na3PO4 + H2O

• H3PO4 + 3NaOH Na3PO4 + 3H2O