If you're seeing this message, it means we're having trouble loading external resources for Khan Academy.
If you're behind a web filter, please make sure that the domains
*.kastatic.org and *.kasandbox.org are unblocked.
Balancing chemical equations
We are now going to look at chemical reactions. But as we do, we need to make sure that atoms aren't magically appearing or disappearing. Put another way, we need to sure that we have the same number of each constituent atom in the product of the reaction as we do in the reactants (the molecules that react)!
How to balance a chemical reaction by making sure you have the same number of atoms of each element on both sides.
Example of balancing the combustion reaction of ethylene. Some tips on how to balance more complicated reactions.
Relating the balanced chemical equation to the structural formulas of the reactants and product.s.
Balancing the combustion reaction of ethane.
Using the substitution method to balance a reaction where a reactant and product have a polyatomic ion in common.
Practice balancing chemical equations