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Balancing Ionic Equations
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Balancing Ionic Equations
Ionic equations are chemical equations which shows the conversion of the reactants into new substances (products).
How to Balance
We will be balancing:
C H + O → CO + H O
3 8 2 2 2
Step 1: Count atoms on both sides:
There are two sides to this equation, the reactant side and the product side. The reactant side is on the left. These are the atoms which are combining to make the products. The products side is on the right.
The goal of balancing equations is to get an equal number of atoms on both sides. The subscript tells you the amount of atoms of that specific substance.
Count the atoms:
Reactants: Products:
C-3 C-1
H-8 H-2
O-2 O-3
Step 2: Choose the first atoms that you will make equal:
In this example, we will start with hydrogen. We start with hydrogen because it is in two of the compounds in our equation. There are two hydrogen atoms on the product side and eight on the reactant side. To get an equal number of hydrogen atoms, we multiply H O by four. To show multiplication, write "4" in front of H O
However doing this will also multiply the oxygen by four. Recount the atoms on the products side:
Products:
C-1
H-8
O-6
C H + O → CO + 4H O
2
2
3 8 2 2 2
Now both sides have an equal number of hydrogen and oxygen atoms. (Check by recounting atoms between steps).
Step 3: Balance the next atom (carbon):
Now we will balance the carbon atoms because carbon is also in two compounds in this equation. There are three carbon atoms on the reactant side and one on the product side. Multiply CO on the product side by three to get three atoms on both sides.
2
C H + O → 3CO + 4H O
3 8 2 2 2
2
2
Step 4: Balance the next atom (oxygen):
Now we will balance oxygen. (recount atoms between steps if needed). Multiplying CO by three multiplies oxygen by three as well. There are now two oxygen atoms on the reactant side and 10 on the product side. (four oxygen atoms in 4H O + 6 oxygen atoms in 3CO ).
Multiply O on the reactant side by "5" to get ten atoms
2
2
C H + 5O → 3CO + 4H O
3 8 2 2 2
Step 5: Check by recounting all atoms:
Reactants: Products:
C-3 C-3
H-8 H-8
O-10 O-10
If there are an equal number of atoms on both sides of the equation, you have balanced it correctly.
Remember To:
Balancing Ionic Equations
- Recount atoms in between steps
- Rewrite the equation as you go
- Double check number of atoms when finished