redox

 

✅ What is a Redox Reaction?

(Class 10 Science – Chapter: Chemical Reactions and Equations)

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📘 Definition (CBSE Standard):

A Redox Reaction is a chemical reaction in which oxidation and reduction take place simultaneously.

• One substance is oxidised (gains oxygen or loses hydrogen)

• Another substance is reduced (loses oxygen or gains hydrogen)

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🔁 Breakdown of the Term “Redox”:

Part	Meaning
Red	Reduction – Loss of oxygen / gain of hydrogen
Ox	Oxidation – Gain of oxygen / loss of hydrogen

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🧪 Example of a Redox Reaction (from NCERT):

$$\text{CuO} + \text{H}_2 \xrightarrow{\text{Heat}} \text{Cu} + \text{H}_2\text{O}$$

Substance	Process	Reason
CuO	Reduction	Loses oxygen to form Cu
H₂	Oxidation	Gains oxygen to form H₂O

✅ Since both oxidation and reduction occur in the same reaction → it is a Redox Reaction.

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📌 More Examples:

1. Zinc and Copper Sulphate Reaction:

$$\text{Zn} + \text{CuSO}_4 \rightarrow \text{ZnSO}_4 + \text{Cu}$$

• Zn is oxidised (loses electrons)

• Cu²⁺ is reduced (gains electrons)

2. Carbon and Zinc Oxide:

$$\text{ZnO} + \text{C} \rightarrow \text{Zn} + \text{CO}$$

• ZnO is reduced

• C is oxidised

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🧠 CBSE Exam Tip:

Q: What is a redox reaction? Give one example.
✅ Answer:
A redox reaction is a chemical reaction in which oxidation and reduction occur simultaneously.
Example:

$$\text{CuO} + \text{H}_2 \rightarrow \text{Cu} + \text{H}_2\text{O}$$

Here, CuO is reduced, and H₂ is oxidised.

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🧩 How to Identify a Redox Reaction:

Look for	Clue
Gain of oxygen	Oxidation
Loss of oxygen	Reduction
Gain/loss of hydrogen	Redox clue
Both occurring in one equation	Redox reaction confirmed

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Let me know if you'd like a comparison table of oxidation, reduction, and redox, or a worksheet for revision!