A balanced chemical reaction is a chemical equation that has equal numbers of each type of atom on both sides of the arrow.
Chemical equations are representations of chemical reactions. They represent the reactants and products in terms of their respective chemical formulae. A chemical equation is a written symbolic representation of a chemical reaction.
The reactants are the substances that undergo reaction, and their formulas are placed on the left side of the equation.
The reactions produce products, which are the substances that are made. The formulas for the products are found on the right side of the equation.
Each reaction formula on its own has a plus sign to separate individual reactant and product formulas, and an arrow (→) separates the reactant and product (left and right) sides of the equation.
The coefficients of reactant and product species are represented by numbers that are placed immediately to the left of each formula. A coefficient of 1 is typically omitted.
The balanced reaction of ethane (C2H6) with oxygen to yield H2O and CO2.
C2H6 + O2 → 3H2O + 2CO2
The Law of conservation of mass governs the balancing of a chemical equation. According to the law of conservation of mass, mass cannot be created nor destroyed; it can only change states. There are three ways that a substance’s mass can change. One way is through chemical reactions. Another is by heat transfer, and the third way is by volume change. It states that the total amount of mass in an isolated system remains constant.
Chemicals should not be allowed to go unbalanced for too long. Chemicals need to be balanced in order to adhere to the law of conservation of mass, which states that mass can neither be created nor destroyed. So the total mass of substances before the chemical reaction should be equal to the total mass of reactants after the reaction. Thus, a chemical equation should be balanced.