All About Chemical Formulas and Chemical Equations

Chemical Formulas

A chemical formula represents the different atoms within a compound. Chemical formulas display information using symbols, numbers and + & – (used to represent positive and negative charges.

The numbers within a chemical formula represent the atomic ratios. This means the amount of one type of atom compared to the amount of another type of atom. For example, H2O has a ratio of two hydrogen to one oxygen.

Chemical Formulas

Chemical Equations

In chemistry there are two types of equations:

  1. Chemical equations
  2. Word equations

Chemical Equations

Chemical equations use symbols and formulas to make an equation

Example:  H2 + O = H2O

Example 2: HCL + NaOH = NaCl + H2O

It is very important to ensure that chemical equations are balanced on both sides. This means that each atom must be accounted for. For example, when you combine carbon and oxygen you get CO2. This is balanced as there is one carbon and two oxygen atoms in carbon and oxygen.

Chemical Equations

Word Equations

Word equations in chemistry represent the names of the elements.

For example: Hydrogen + Oxygen = Water

The symbol + means ‘and’ and the = means ‘turns into’

There are two types of chemicals in word equations reactants and products. Reactants are the chemicals that react with each in order to produce something. For example, hydrogen and oxygen are reactants when creating water.

Products are what the chemical reactions create. For example, when hydrogen and oxygen react with each other; they create the product water.

Reactants = Products

Word Equations

See Chemical Formulas and Equations Worksheet