Understanding coefficients and subscripts is essential when balancing equations (and for many other topics in chemistry). In this video you learn the difference and how to correctly use both.

- Coefficients are used for balancing equations. They are the number in front of compounds or elements.
- Subscripts come after the element symbol and indicate the number of that element. In H
_{2}O the "2" means there are two H atoms. - If there is no subscript after an element symbol, we assume it to be "1". In H
_{2}O this means there is "1" O atom.

When balancing chemical equations our goal is to have the same number of each type of atom on both sides of the equation.

You can only change the coefficients when balancing!Balanced equations provide **ratios** between substances. The coefficients can be thought of as ** mole ratios**.