How to Balance Chemical Equations

Balancing Chemical Equations involves understanding concepts and learning basic skills required in Chemistry. Though balancing chemical equations is very simple however it requires practice.

Chemical equations are required to be balanced because a balanced chemical equation demonstrates and verifies the law of conservation of mass or matter.

The law of conservation of matter states that matter cannot be created nor destroyed but can be transformed from one form to another.

law of conservation of matter

It is important to buttress that chemical reactions are always meant to be balanced in chemistry and Stoichiometry calculations also need to be balanced before calculations.

I know there are a lot of rules you must have read across different articles or even videos but I will make this thing very simple for you.

I will talk about just 4 rules that we will just have to adhere to throughout our balancing of chemical equations.

Rules of Balancing Chemical Equations

1. Do not change the subscript in the molecule i.e changing the atomicity or formula of compounds or molecules
2. Do not write a number in between the atoms
3. Put a number as coefficients in front of the molecule or compounds
4. Practice balancing a few equations

Balancing is a skill so the more you practice the better you get at it.

Examples of Balancing Chemical equations

Please remember that the aim is to have an equal number of atoms on both sides of the equation.

Module 1: Balancing very simple chemical equations

1. Formation of steam

H₂ + O₂ à H₂O

Balancing

2H     2O        =     2H     1O

Oxygen is not balanced i.e equal

The first temptation is to PUT subscript 2, avoid it.

Do not do this         H₂ + O₂ à H₂O₂

So what should I do?

Only put a number in front, always remember!

So this will give me

H₂ + O₂ à 2H₂O

Let’s analyze again

H₂ + O₂ à 2H₂O

2H     2O        =     4H     2O

We succeeded in balancing oxygen but then we did upset or unbalance hydrogen.

We need to make hydrogen equal.

2H₂ + O₂ à 2H₂O

Now balanced   4H     2O        =     4H     2O

• Formation of Ammonia

N₂ + H₂  à      NH₃

Balancing

2N 2H             = 1N 3H

What should I do?

Start by balancing nitrogen

Put 2 in front of ammonia

N₂ + H₂  à     2NH₃

Analysis

2N 2H   = 2N 6H

I need to balance hydrogen in ammonia

Put 3 in front of hydrogen

N₂ + 3H₂  à     2NH₃

Balanced

2N 6H   = 2N 6H

Module 2: Balancing equations involving three products

• Reaction of a metal with an acid

 Zn + HCl à ZnCl₂ + H₂

Balancing

1 Zn 1H 1Cl   = 1Zn 2Cl 2H

I  just simply need to balance hydrogen and chlorine.

Put 2 in front of HCl

Zn + 2HCl à ZnCl₂ + H₂

• Reaction of acids with carbonates

HCl + CaCO₃  à CaCl₂ + H₂O + CO₂

Balancing

1H  1Cl  ICa  1C 3O  = 1Ca 2Cl 2H  3O

I just need to balance hydrogen and chlorine

Simply put 2

2HCl + CaCO₃  à CaCl₂ + H₂O + CO₂

Some equations may look hard but actually easy to balance, some just require sall numbers and then you are done balancing it.

I will update this post by showing us how to balance complex chemical equations.