*Chapter 3: Metals and Non-metals*
*Complete Notes*
*1. Metals kya hote hain?*
Jo elements heat aur electricity conduct karte hain, shiny hote hain, aur hammer se patle
sheet ban jate hain, unhe metals kehte hain.
Examples: Iron, Copper, Aluminium, Gold, Silver
*2. Non-metals kya hote hain?*
Jo elements heat aur electricity conduct nahi karte, dull hote hain, aur todne par toot jate
hain, unhe non-metals kehte hain.
Examples: Oxygen, Carbon, Sulphur, Chlorine
*3. Metals ke Physical Properties:*
- Shiny/lustrous hote hain
- Malleable: patli sheet ban sakti hai
- Ductile: patla wire ban sakta hai
- Heat aur electricity ke good conductors
- Sonorous: thokne par awaz karte hain
- High melting and boiling point (Mercury ko chhod kar)
*4. Non-metals ke Physical Properties:*
- Dull hote hain, graphite ko chhod kar
- Brittle: todne par toot jate hain
- Poor conductors of heat and electricity
- Low melting and boiling point
*5. Chemical Properties of Metals:*
- Oxygen se react karke metal oxide banate hain: 4Na + O2 → 2Na2O
- Water se react karke metal hydroxide + H2 gas: 2Na + 2H2O → 2NaOH + H2
- Acid se react karke salt + H2 gas: Zn + H2SO4 → ZnSO4 + H2
*6. Reactivity Series:*
Potassium > Sodium > Calcium > Magnesium > Aluminium > Zinc > Iron > Copper > Silver
> Gold
Jo upar hai wo zyada reactive hai.
*7. Important Points for Exam:*
- Ionic bond metal aur non-metal ke beech banta hai
- Aluminium oxide layer banne se corrosion nahi hota
- Gold aur Platinum least reactive metals…