reactivity order

 Absolutely, Mayank! Here's a CBSE Class 10–style explanation of why zinc and lead can displace copper from its compounds, using clear reasoning, the reactivity series, and additional examples to help students grasp the concept deeply.

🔁 Why Can Zinc and Lead Displace Copper from Its Compounds?

(Chapter 1: Chemical Reactions and Equations – Class 10 Science)

🎯 Key Concept: Reactivity Series

The reactivity series is a list of metals arranged in decreasing order of their chemical reactivity.

  • A metal higher in the series can displace a metal lower in the series from its salt solution.

  • This is because it has a greater tendency to lose electrons and form positive ions (more reactive).

🧪 Reactivity Series (Top to Bottom) (Partial)

Potassium (K)  
Sodium (Na)  
Calcium (Ca)  
Magnesium (Mg)  
Aluminium (Al)  
**Zinc (Zn)**  
**Iron (Fe)**  
**Lead (Pb)**  
**Copper (Cu)**  
Mercury (Hg)  
Silver (Ag)  
Gold (Au)

✅ Zinc (Zn) and Lead (Pb) are above Copper (Cu) → more reactive

🔄 What This Means:

Because zinc and lead are more reactive than copper, they can push copper out from its compounds — a displacement reaction.

📘 Examples to Prove This:

✅ 1. Zinc Displaces Copper from Copper Sulphate

Zn (s)+CuSO4(aq)→ZnSO4(aq)+Cu (s)\text{Zn (s)} + \text{CuSO}_4 (aq) \rightarrow \text{ZnSO}_4 (aq) + \text{Cu (s)}

  • Zinc replaces copper in its compound.

  • Copper metal deposits, and the blue colour fades.

✅ 2. Lead Displaces Copper from Copper Chloride

Pb (s)+CuCl2(aq)→PbCl2(aq)+Cu (s)\text{Pb (s)} + \text{CuCl}_2 (aq) \rightarrow \text{PbCl}_2 (aq) + \text{Cu (s)}

  • Lead is more reactive than copper, so it displaces copper.

🚫 3. Copper Cannot Displace Zinc or Lead

Cu (s)+ZnSO4(aq)→No reaction\text{Cu (s)} + \text{ZnSO}_4 (aq) \rightarrow \text{No reaction} Cu (s)+Pb(NO3)2(aq)→No reaction\text{Cu (s)} + \text{Pb(NO}_3)_2 (aq) \rightarrow \text{No reaction}

  • Copper is less reactive, so it cannot displace zinc or lead.

🧠 Real-Life Application:

  • This principle is used in metal extraction, corrosion prevention, and electroplating.

  • For example, iron is galvanized with zinc — zinc sacrifices itself to protect iron from rusting.

📚 CBSE Exam Style Q&A:

Q: Why can zinc displace copper from copper sulphate, but copper cannot displace zinc from zinc sulphate?

✅ Answer:
Zinc is more reactive than copper (higher in the reactivity series), so it displaces copper from copper sulphate solution. Copper is less reactive, so it cannot displace zinc.

🎤 Final Classroom Thought:

“In the chemistry of metals, strength is everything — and zinc or lead always take copper’s place because they’re higher in the reactivity race!”

Would you like this explained using a reactivity series poster, a student flowchart, or a lab demo script for copper sulfate displacement activities?

Comments

Post a Comment

Popular posts from this blog

⚡ Electrolytic Decomposition Reaction

Certainly, Mayank! Here's a Class 10–level explanation of Electrolytic Decomposition Reaction , aligned with the CBSE syllabus and written in a clear, engaging, and exam-ready format for your students. ⚡ Electrolytic Decomposition Reaction (From Chapter 1: Chemical Reactions and Equations – Class 10 Science) 🎯 Definition: An electrolytic decomposition reaction is a chemical reaction in which a compound is broken down into simpler substances using electricity . ✅ The process of using electric current to split a compound is called electrolysis . 📘 General Reaction Format: A B → Electricity A + B AB \xrightarrow{\text{Electricity}} A + B 🧪 Example: Electrolysis of Water (As shown in NCERT Activity 1.7) 2 H 2 O (l) → Electricity 2 H 2 ( g ) + O 2 ( g ) 2\text{H}_2\text{O (l)} \xrightarrow{\text{Electricity}} 2\text{H}_2 (g) + \text{O}_2 (g) Water (H₂O) splits into: Hydrogen gas (H₂) → collected at cathode Oxygen gas (O₂) → collected at anode The ...
Read more

🔥 Activity 1.11 – Oxidation and Reduction (Redox Reaction)

 Certainly, Mayank! Here's a CBSE Class 10–aligned explanation of Activity 1.11 , along with an answer to the Recall of Activity 1.1 . The focus is on conceptual clarity, oxidation-reduction (redox) concepts, and exam readiness. 🔥 Activity 1.11 – Oxidation and Reduction (Redox Reaction) (Class 10 Science – Chapter 1: Chemical Reactions and Equations) 🎯 Objective: To demonstrate how a metal (copper) undergoes oxidation and how the product can be reduced using hydrogen gas. 🧪 Materials Required: Copper powder (about 1 gram) China dish Heat source (burner or spirit lamp) Hydrogen gas (for part 2 of the reaction) 🔬 Procedure: Take a small quantity of copper powder in a china dish . Heat the copper gently. Observe any colour change. Now, pass hydrogen gas over the heated copper oxide . 👁️ Observations: Step What Happens Chemical Equation 1. Heating copper Surface turns black due to formation of copper(II) oxide (CuO) 2 Cu...
Read more

🧪 Precipitation Reaction

 Certainly, Mayank! Here's a clear, CBSE-exam–oriented explanation of the Precipitation Reaction for Class 10 Science students, with definitions, examples, and concepts aligned with the NCERT syllabus. 🧪 Precipitation Reaction (Class 10 Science – Chapter 1: Chemical Reactions and Equations) 📘 Definition: A precipitation reaction is a type of chemical reaction in which two aqueous solutions react to form an insoluble solid called a precipitate . ✅ This precipitate appears as a solid that settles at the bottom of the reaction mixture. 🔬 General Form: A B ( a q ) + C D ( a q ) → A D ( s ) ↓ + C B ( a q ) AB (aq) + CD (aq) \rightarrow AD (s) ↓ + CB (aq) AB and CD are aqueous ionic compounds AD is the precipitate (solid) CB remains dissolved in water (aqueous) 🧪 Examples from NCERT / CBSE Class 10: ✅ 1. Barium Chloride + Sodium Sulphate (Activity 1.10) BaCl 2 ( a q ) + Na 2 SO 4 ( a q ) → BaSO 4 ( s ) ↓ + 2 NaCl ( a q ) \text{BaCl}_2 (aq) + \te...
Read more