Take out a piece of paper and a pencil and go through this example with me. We will use algebra to solve for the coefficients. It's a 6-step process.
| When propyl alcohol, CH3CH2CH2OH, burns in air, it reacts with oxygen, O2, to form carbon dioxide, CO2, and water, H2O. Write the balanced chemical reaction. |
Otherwise, let's begin:
| Step 1 | Identify the reactants and products. | |
|---|---|---|
| Step 2 | Write the unbalanced chemical equation. | |
| Step 3 | Assign variables as coefficients for each substance in the chemical equation. | |
| Step 4 | Determine the number of each type of atoms on
each side of the arrow.
| |
| Step 5 | Write out the algebraic equations and solve for the coefficients. | |
| Step 6 | Make sure that all the coefficients are whole numbers. Multiply all the coefficients by an appropriate factor to convert any fractions to whole numbers. |
The balanced chemical equation is:
2
CH3CH2CH2OH (l) +
9O2 (g) -->
6CO2 (g) +
8H2O (l)