🔥 Chapter 3: Metals and Non-Metals
🎯 Class 10 Science Best Notes (With Hindi Explanation)

🧲 1. Physical Properties of Metals and Non-Metals

🔹 Metals

• Hard, shiny, malleable (can be beaten into sheets), ductile (can be drawn into wires), good conductors of heat and electricity.
  👉 Hindi: Metals kadak, chamakdaar, patle sheet aur wire ban sakte hain. Bijli aur garmi ke ache conductor hote hain.
  🔸 Example: Iron, Copper, Aluminium
  
  

🔹 Non-Metals

• Soft, dull, brittle (breakable), poor conductors.
  👉 Hindi: Non-metals naram, bina chamak ke, todne par toot jaate hain, aur ache conductor nahi hote.
  🔸 Example: Sulphur, Carbon, Oxygen
  
  

🧪 2. Chemical Properties

🔹 (i) Reaction with Oxygen

• Metal + O₂ → Metal Oxide (basic in nature)
  Example: 4Na + O₂ → 2Na₂O
  
  

• Non-metal + O₂ → Non-metal Oxide (acidic in nature)
  Example: C + O₂ → CO₂
  👉 Hindi: Metals oxygen se milkar basic oxide banate hain aur non-metals acidic oxide.
  
  

🔹 (ii) Reaction with Water

• Metals react with water to form metal hydroxide and hydrogen gas.
  Example: 2Na + 2H₂O → 2NaOH + H₂↑
  
  

• Most non-metals do not react with water.
  
  

🔹 (iii) Reaction with Acids

• Metal + Acid → Salt + H₂ gas
  Example: Zn + H₂SO₄ → ZnSO₄ + H₂↑
  
  

• Non-metals generally do not react with acids.
  
  

🔹 (iv) Reaction with Bases

• Some metals react with bases to release hydrogen gas.
  Example: Zn + 2NaOH → Na₂ZnO₂ + H₂↑
  
  

🔁 3. Displacement Reaction
More reactive metals displace less reactive metals from their salt solution.
Example: Zn + CuSO₄ → ZnSO₄ + Cu
👉 Hindi: Zyada reactive metal kam reactive metal ko uske compound se hata deta hai.

🏭 4. Occurrence of Metals

🔹 Metals found in nature as:

• Free state – e.g., Gold, Platinum
  
  

• Combined state – e.g., Iron in the form of ores like hematite (Fe₂O₃)
  
  

⚙️ 5. Extraction of Metals

🔸 Steps:
(i) Concentration of ore – Removing impurities
(ii) Calcination or Roasting – Heating the ore
(iii) Reduction – Getting pure metal from its ore
(iv) Refining – Purification of metal

🧪 6. Corrosion
When metals react with air and moisture, they get corroded.
Example: Iron → Rust (Fe₂O₃·xH₂O)
👉 Hindi: Loha hawa aur nami se milkar zung banata hai.

Prevention:

• Galvanization, Painting, Oiling
  
  

🔬 7. Properties of Ionic Compounds

• Made by transfer of electrons (metal donates, non-metal gains)
  
  

• High melting and boiling point
  
  

• Soluble in water
  
  

• Conduct electricity in molten/solution form
  👉 Hindi: Ionic compound electron transfer se banta hai, yeh soluble hote hain aur electricity conduct karte hain.
  
  

📘 Important Questions for Practice — With Answers

✅ 1 Mark Questions

1. Name a metal that can be cut with a knife.
   👉 Sodium
   
   

2. What is formed when iron reacts with moist air?
   👉 Rust (Fe₂O₃·xH₂O)
   
   

3. Define corrosion.
   👉 Slow destruction of metal due to air and moisture.
   
   

✅ 2 Mark Questions

1. What is an alloy? Give one example.
   👉 Alloy is a mixture of metals or metal with non-metal.
   Example: Brass (Copper + Zinc)
   
   

2. Why are ionic compounds hard and have high melting points?
   👉 Due to strong electrostatic forces between ions.
   
   

✅ 3 Mark Questions

1. Explain the steps of extraction of metals from their ores.
   👉 (i) Concentration (ii) Calcination/Roasting (iii) Reduction (iv) Refining
   
   

2. What are the physical differences between metals and non-metals?
   👉 Metals: Hard, malleable, ductile, good conductors
   👉 Non-metals: Soft, brittle, poor conductors
   
   

✅ 5 Mark Questions

1. Describe the chemical properties of metals and non-metals.
   👉 Reaction with oxygen, water, acids, and bases (examples included above)
   
   

2. Explain ionic bond formation with an example.
   👉 Sodium donates electron to chlorine → Na⁺ + Cl⁻ → NaCl
   👉 Hindi: Metal apna electron deta hai aur non-metal leta hai, jisse ionic bond banta hai.