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If the things are perfect in our world, it is because of the ever-going chemical reactions. The different types of chemical reactions are vital for our culture, technology, and life.

Smelting iron, burning fuels, pottery and glass manufacturing, production of cheese and wine, and brewing processes are typical chemical reaction examples. We balance complex chemical equations for getting desired results.

These processes have been used for thousands of years. There are many conversion or chemical factors are involved in this. It force us to think what is a chemical reaction, what are the types of chemical reactions and how it works? But to understand the process, you first have to learn the ropes.

Related: This website helps you with other equation balancing calculators like with theoretical yield calculator and percent yield calculator, you can find the yield percentage within a chemical reaction.

What is a chemical reaction?

A chemical reaction is as a process in which one or more substances undergo a chemical change. Such change can be in the structure or positioning of atoms.

So, one or more new substances come into being. The substances involved in the reaction are reactants and resulting substances are products. A common chemical reaction example is

A + B (reactants) → AB (products)

These substances could be either chemical compounds or elements. The simplest chemical reaction examples happening in our surroundings are as follows.

H2 + O2 → 2H2O (between elements)
2Na + Cl2 → 2NaCl (between elements)
HCl + NaOH → NaCl + H2O (between compounds)

Also find how to write a net ionic equation and how redox reaction balancer calculator helps you to balance redox equations.

What are the types of Chemical Reactions in Chemistry?

There are 5 types of chemical reactions in chemistry which are important. Among different types of reaction in chemistry, these 5 types of chemical reactions are widely used for understanding.

The changes which occur within the reactants during a chemical reaction determine the types of chemical reaction and the nature of products.

Based on this rule, chemical reactions are often divided into five common types.

Most of the products we get in our daily lives come into existence by going through one of these five reactions.

And if a person learns about these basic chemical reactions, dealing with chemical equations would not be a problem. The list of chemical reactions in chemistry is as follows

  • Combination reaction
  • Decomposition reaction
  • Combustion reaction
  • Single replacement reaction
  • Double replacement reaction


The question which arises here is how someone can predict the type of chemical reactions in chemistry by seeing a chemical equation?

Answer: Analyze the nature of reactants and products taking part in the reaction. You will be able to predict the types of reaction occurring among them. In some cases, there are even such reactions that fall into more than one category.

Related: Learn all about hydrogen emission lines and dna double helix available in a blog section.

Combination reaction

Combination reaction is a type of chemical reaction. In combination reaction, two or more substances combine to form a single and all-new substance.

Since a new substance is being synthesized, such reactions referred as synthesis reactions. Let's have a look at the general equation of combination reaction for illustration.

A + B → AB

Some common combination or synthesis reaction examples are as follows

2Na + Cl2M → 2NaCl
2Zn + O2 → 2ZnO
H2 + O2 → 2H2O

Periodic table plays a vital part in the process of chemical reaction. Learn more about the histroy and importance of periodic table. Also learn what is capillary gel electrophoresis and its role while splitting ions.

Quick tips:

  • Always remember that in combination reactions, two elements react to form a compound. So, whenever you notice a chemical reaction where two elements interact to form a single compound, know that it is a combination reaction. This can be processed by using chemical equation calculator online.

Related: What is the general chemical equation for an endothermic reaction?

Decomposition reaction

The term "decompose" means "to break down." In decomposition reactions, a single substance breaks into its constituents or smaller units.

In such sort of reactions, the reactant is always a bigger chemical compound that comprises many elements. These elements may get separated from each other simply, such as

AB → A + B

Or may broke into simpler substances such as

ABX → AB + X

The common examples of decomposition reactions are as follows

CaCO3 → CaO + CO2
2H2O → H2 + O2
2AgBr → 2Ag + Br2

Find useful other calculators to increase your productivity and efficiency regarding chemical calculations, use oxidation state calculator and percent composition by mass calculator free on this website.

Quick tips:

  • Remember that the binary compounds always break into two elements while bulkier compounds form latterly.
  • Whenever you notice that there is only one reactant in the reaction mixture, which is getting broken down into simpler units, know that decomposition is occurring.
  • Decomposition reactions are nothing other than the reversed combination reactions.

Related: How to balance chemical equations step by step?

Combustion reaction

Whenever the term combustion appears, always think of a burning process. In this type of chemical reaction, a chemical substance reacts with oxygen and burns into simpler units. They release energy in the form of heat and light.

The simplest of chemical reaction example is the burning of fossil fuel. The fuel burns in the presence of oxygen and releases energy along with by-products.

Hydrocarbons + oxygen → carbon dioxide + water + heat
CH4 + 2O2 → CO2 + 2H2O
C3H8 + 5O2 → 3CO2 + 4H2O

Quick tips:

  • All the reactions where energy is released in heat and light is due to the combustion phenomenon.
  • Combustion of hydrocarbons always results in products such as water and carbon dioxide.
  • Oxygen is always present at the left side of the equation in combustion reactions.

Related: Complete process for finding oxidation state of an element.

Single-replacement reaction

In this type of chemical reaction, one element from one of the reactants detaches and bind to another reactant such as follows

AC + B → A + BC

As indicated by the equation, C detaches from the first reactant (AC) and gets attached to the B to form the final product (BC).

Since element A replaces element B, the reaction refers to as a replacement reaction. Some examples of single replacement reactions are as follows

Zn + 2HCl → ZnCl2 + H2
Br2 + 2KI → 2KBr + I2

Quick tips:

  • Metal can only replace another metal atom, as described in the above general equation. If A is metal, B will be a metal atom. Read this article to learn more about metal displacement reaction.
  • A non-metal will always replace another non-metal. So if confused about the final products of a single replacement reaction. Analyze the nature of replacing elements to predict the correct product.
  • When a single replacement reaction occurs between metal and acid, hydrogen gas is formed as a by-product along with the main replacement product. Such as
    Zn + 2HCl → ZnCl2 + H2 (g)

Related: How to balance redox reaction in a basic solution?

Double replacement reaction

Such chemical reactions always take place between ionic compounds. As the name implies, two atoms get replaced in the reactants.

Since the ionic compounds are reacting with each other, the replacement of positive and negative ions of each compound occur to form new compounds such as

A+B- + C+D- → C+B- + A+D-

Some examples of double replacement reactions are as follows

AgNO3 + NaCl → NaNO3 + AgCl (ppt.)
KBr + AgNO3 → KNO3 + AgBr (ppt.)

Related: Step wise process of finding percentage yield.

Quick tips:

  • Double replacement reactions always occur in aqueous solutions. After replacement, the two products separate from each other since one of them comes out as sediment.
  • When you observe a chemical reaction where ion-displacement occurs, and at least one final product comes out as sediment. It means the reaction occurring between them is a double replacement reaction.

We hope this article helped you a lot in understanding chemical reactions and its types. Find useful other blogs on different chemistry topics. You can also use free calculators on this website like molecular weight calculator and titration volume calculator can help you to learn and practice online.