Balancing Chemical Equations
|
Balancing equations is a necessary skill in chemistry and it reflects the fact that matter is neither created nor destroyed, according to the law of conservation of mass (Thank you Antoine Laurent Lavoisier). Simply put, the number atoms before and after reaction does not change. Atoms are not lost. Antoine Laurent Lavoisier showed that
although matter changes its state, its quantity
remains constant throughout a chemical reaction. He was a French chemist,
born in |
|
Consider
the following reaction where water is broken down into oxygen gas and hydrogen
gas:
|
Water |
à |
Oxygen Gas |
+ |
Hydrogen Gas |
|
H20 |
|
02 |
+ |
H2 |
The formula for each molecule above is correct. However, as you can see, it seems that we have gained an extra oxygen atom. This is not possible. Something is wrong.
Balancing this equation will satisfy the law of conservation of mass. See the solution below:
|
Water |
à |
Oxygen Gas |
+ |
Hydrogen Gas |
|
2H20 |
|
02 |
+ |
2H2 |
Write
a 2 before the water molecule. 2 water molecules can result in 1 oxygen gas molecule
after reaction. As you can see, the number of oxygen atoms is the same before
and after reaction.
Lastly,
if we write a 2 before the hydrogen gas molecule, we will have balanced the
number of hydrogen atoms before and after reaction. The total number of atoms
is the same before and after reaction.
Practice balancing equations: Balancing Chemical Equations Simulation
More Practice balancing equations: Balancing Chemical Equations Rags to Riches Game
Even More Practice: http://funbasedlearning.com/chemistry/chembalancer/default.htm
Another Conservation of Mass Link: Conservation of Mass