A redox reaction is a chemical reaction whereby both oxidation & reduction occurs simultaneously.

The word “REDOX” comes from the words REduction and OXidation.

So, how do you know if a redox reaction has taken place?

There can be more than one way of identifying a particular chemical reaction as a redox reaction. This also mean that not all chemical reactions are redox reactions.

4 Ways to Identify a Redox Reaction

1) Gain or loss of oxygen

2) Gain or loss of hydrogen

3) Gain or loss of electrons

4) Increase or decrease in oxidation state

Oxidation has taken place if a substance:

• gains oxygen
• loses hydrogen
• loses electrons
• increases its oxidation state after a reaction

Reduction has taken place if a substance:

• loses oxygen
• gains hydrogen
• gains electrons
• decreases its oxidation state after a reaction

In the following YouTube Video, you will learn EVERYTHING you need to know to determine whether a chemical reaction involves redox reaction. This video is exactly what we taught Sec 3 and Sec 4 students in our O-Level Pure Chemistry Tuition Classes. This applies to IP and IGCSE students in our classes as well.

Step-by-step strategies as well as some common rules are also being discussed when it comes to gain/loss of electrons and increase/decrease in oxidation state.

Do note that questions based on gain/loss of electrons and increase/decrease in oxidation state tends to be more tricky in Chemistry examination.

Length of video: 16.02 minutes

Direct video link: https://youtu.be/sUU1YSnWBnQ

I hope you find the content easy for your understanding and if you have any questions, leave me a comment below. Feel free to share this blog post with your friends and learn the key O-Level Pure Chemistry concepts together.

In the next blog post, i will be sharing with you on the concepts of Oxidising Agents and Reducing Agents, and also how to identify them using common reagents in the school laboratories.

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PS: Under related articles below, there are several blog post discussions and questions related to Redox Reaction concepts. I will list some of these older blog posts below.

Redox Reaction based on Oxygen Atoms

Redox Reaction based on Hydrogen Atoms

Tips on Assigning Oxidation States

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