Chapter 4: Dhaatu aur Adhaatu ki Duniya
Lohaar ki bhatti se Dilli ke Lauh Stambh tak, dhaatuein hamari zindagi gadhti hain. Is chapter mein padaarthon ki chamak, malleability, ductility, sonority aur chaalan jaanchenge, dekhenge hawa aur paani loha kaise jung lagaate, magnesium aur gandhak jalaakar unke oxide milaayenge, aur jaanenge adhaatu bhi utne hi zaroori kyun.
Is chapter mein tum
- dhaatu aur adhaatu ke gun milaana
- malleability, ductility, sonority aur chaalan samjhaana
- jung ki shartein dhoondhna
- dhaatu aur adhaatu oxide milaana aur upyog batana
Topics
- Malleability, Ductility aur Sonority NCERT 4.1.1–4.1.3
Dhaatuein chamakdaar, malleable (chaadar), ductile (taar) aur sonorous (khanak).
- Garmi aur Bijli ka Chaalan NCERT 4.1.4–4.1.5
Dhaatuein garmi aur bijli achchhi chalaati; gandhak, koyla jaise adhaatu nahi.
- Dhaatuon par Hawa aur Paani ka Asar NCERT 4.2–4.3
Loha sirf hawa aur paani dono se jung khaata; jung corrosion ka ek roop.
- Adhaatu aur Unke Upyog NCERT 4.4–4.5
Adhaatu feeke, bhangur, kharaab chaalak aur acidic oxide banaate.
Key words
- Lustre
- dhaatuon ki chamak
- Malleable
- chaadar mein peeta ja sake
- Ductile
- taar mein kheencha ja sake
- Sonorous
- khanakti aawaaz
- Brittle
- maarne par toot jaaye
- Corrosion / rusting
- hawa-paani se dhaatu ka dheema nuksaan; lohe par jung
- Element
- jo saral padaarthon mein na toote
Summary
- Dhaatu: chamakdaar, sakht (zyaadatar), malleable, ductile, sonorous, achchhi chaalak.
- Adhaatu: feeke, bhangur, kharaab chaalak.
- Loha nam hawa mein jung khaata; dhaatu oxide basic, adhaatu oxide acidic.
- Oxygen, carbon, nitrogen, chlorine, iodine jaise adhaatu zaroori.