Why should the equation be balanced?

Chemical reactions involve the breaking and formation of bonds between atoms. In any chemical reaction, the law of conservation of mass must be obeyed, which states that matter can neither be created nor destroyed. Therefore, the number of atoms of each element present in the reactants must be equal to the number of atoms of each element present in the products. This is where the concept of balancing the equation comes in.

Types of Chemical Reactions

There are five main types of chemical reactions:

1. Combination or synthesis reaction: In this type of reaction, two or more reactants combine to form a single product. The general equation for a combination reaction is A + B → AB.

2. Decomposition reaction: In this type of reaction, a single reactant breaks down into two or more products. The general equation for a decomposition reaction is AB → A + B.

3. Single displacement or substitution reaction: In this type of reaction, one element replaces another element in a compound. The general equation for a single displacement reaction is A + BC → B + AC.

4. Double displacement or metathesis reaction: In this type of reaction, two compounds exchange ions to form two new compounds. The general equation for a double displacement reaction is AB + CD → AD + CB.

5. Combustion reaction: In this type of reaction, a fuel (hydrocarbon) reacts with oxygen gas to produce water vapor and carbon dioxide gas. The general equation for a combustion reaction is CxHy + O2 → CO2 + H2O.

Explanation of Balanced Equations

A balanced chemical equation has the same number of atoms of each element on both the reactant and product sides of the equation. In order to balance an equation, one must add coefficients (whole numbers) in front of the chemical formulas to balance the number of atoms of each element.

For example, consider the combustion of methane: CH4 + O2 → CO2 + H2O. In this equation, there are one carbon atom, four hydrogen atoms, and two oxygen atoms on the reactant side, but one carbon atom, two hydrogen atoms, and two oxygen atoms on the product side. To balance the equation, one can add a coefficient of 2 in front of the oxygen molecule: CH4 + 2O2 → CO2 + 2H2O.

In conclusion, balancing chemical equations is important to ensure that the law of conservation of mass is obeyed and that the correct amount of reactants and products are present in a chemical reaction. Understanding the different types of chemical reactions can also help in predicting the products of a reaction and balancing the equation accordingly.

The chemical equation needs to be balanced so that it follows the "Law of conversation of mass". A balanced chemical equation occurs when the number of the different atoms of elements in the reactants side is equal to that of the products side.