What steps can be used to balance a chemical equation?

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combustion — chemical reaction Log burning in a fire. Burning wood is an example of a chemical reaction in which wood in the presence of heat and oxygen is transformed into carbon dioxide, water vapor, and ash.

To balance a chemical equation, you must adhere to the law of conservation of mass, which dictates that the number of atoms for each element must be identical on both sides of the reaction. It is important to note that you should only modify the coefficients (the numbers in front of molecules) to balance an equation. You must never change the subscripts (the small numbers within a chemical formula), as doing so would alter the chemical identity of the substances involved.1

You can balance any equation by repeating these three steps until the atom counts match:1

Step 1: Count the atoms. Determine the number of atoms for each element on both the reactant and product sides. Creating a chart or list can help you visualize these totals.1
Step 2: Change a coefficient. Select one substance and adjust its coefficient to help equalize the number of atoms on both sides. Aim to use the lowest possible whole number and change only one coefficient at a time to avoid confusion.1
Step 3: Recount. Update your atom counts and repeat the process until the equation is balanced.1