# Key Concepts: Balancing Equations using Masses

## Key Concepts: Balancing Equations using Masses

• In chemical reactions, the law of conservation of mass states that no atoms are created or destroyed. Thus, the total mass of the reactants is always equal to the total mass of the products.
• This principle allows us to balance chemical equations. In a balanced equation, there are the same number of each type of atom on both sides of the equation.
• To balance a chemical equation, begin by writing out the unbalanced equation, listing all the reactants and the products.
• Then, count the number of each type of atom on both sides of the equation.
• If there are any imbalances, adjust the coefficients (the numbers in front of the chemical formulae) until each side contains the same number of each type of atom. Iterate this step as needed.
• Never alter the subscripts (the small numbers following the atomic symbols in a chemical formula) as those indicate the number of each type of atom within a single molecule or unit of the substance.
• Remember that the state of matter (i.e., solid, liquid, gas, or aqueous) does not impact the balancing process. However, it should still be indicated in the equation.
• Coefficients refer to the number of molecules (in moles) involved in the reaction, and they are crucial in stoichiometric calculations, which involve converting between the amount of reactants and products in a chemical reaction.
• Understanding how to balance equations using masses will assist in predicting the quantities of reactants needed to produce a certain amount of product, as well as the amount of product that can be produced from a certain amount of reactants.
• Practice is key to get a solid grasp on balancing equations. Start with simple equations and gradually increase the complexity.