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GCSE Science Tutor Booster: Balancing Chemical Equations.

A quick, all you need to know GIF tutorial on balancing chemical equations.

December 6, 2021

Let's face it, all things in life need to balance to work effectively.

And this includes chemical equations. So, first of all, let us recap what a chemical equation is.

A chemical equation consists of the chemical formulas of the reactants (the starting substances) and the chemical formula of the products (substances formed in the chemical reaction). The two are separated by an arrow symbol and each individual substance's chemical formula is separated from others by a plus sign.

For example: Sodium reacts with chlorine to form sodium chloride. This can be shown with the following chemical equation:

 

Magnesium reacts with oxygen to form magnesium oxide. This can be shown with the following chemical equation:

 

However, the above chemical equation is not balanced there is an unequal number of atoms on the left and right side of the equation. Symbol equations must be balanced.

To make things equal adjust the number of units of some of the substances until you get equal numbers of each type of atom on both sides.

The balanced symbol equation for the reaction is therefore:

 

There are two magnesium atoms and two oxygen atoms on the left side of the equation. This equals the two magnesium atoms and two oxygen atoms on the right side of the equation.

Let's take a closer look at how you do this with the next example:

 

 

The diagram helps to show the imbalance on each side of the equation. You can clearly see that the product side of the equation has more aluminium and bromine atoms. To balance the equation you are simply adding more of these atoms to the reactant side of the equation. This is shown below:

 

 

Simple, huh. This is a great technique to use whilst learning and practising how to balance chemical equations. 

OR, you could have a go at this technique:

 

 

Just find the best way that suits you. Practise makes perfect and before you know it you will be balancing chemical equations automatically.