ChemistryBhanu · Class 4-5
Teen keelein, ek prayog: jang kaise lagti hai?
Teen ek jaisi keelein teen alag jagah rakho. Kaun si sabse pehle laal-bhoori hogi?
Socho pehle… phir dekho jawab
Jo keel paani mein aur khuli hawa mein hogi, khaaskar namak wale paani mein. Kyunki jang ke liye loha ko oxygen aur paani dono chahiye, aur namak jang ko tez kar deta hai.
Ravi ko shak tha ki jang sirf paani se lagti hai. Usne maanne se pehle jaanchne ka faisla kiya: teen keelein, teen shartein, aur roz ek chhoti note-book mein likhna.
Cause-effect: jang ek chemical badlav hai. Loha + oxygen + paani milkar ek naya padarth banate hain — jang (hydrated iron oxide). Sookhi hawa mein paani nahi, toh jang bahut dheere lagti hai. Geeli keel mein oxygen aur paani dono hain, toh jang jaldi lagti hai.
Namak wala paani raasta tez kar deta hai, isliye samudra ke kinare ke shehron mein loha jaldi kharab hota hai. Bachav: rang, tel, ya zinc ki parat (jise galvanising kehte hain), taaki loha seedha hawa aur paani se na mile.
Ghar pe try karo
Bade ki madad se teen katori lo: (1) sookhi keel, (2) saade paani mein keel, (3) namak ghule paani mein keel. Keel bade hi rakhein aur uthayein. 3 din roz dekho aur likho kya badla. Dekhne ke baad haath dho lo.
Wow!
Samudra ke paas hawa mein namak ke nanhe kan hote hain, isliye wahan ki loha ki cheezein jaldi jang pakadti hain.
Mummy-Papa ke liye
Aaj bachche ke saath teen katori wala prayog shuru kijiye (keel aap rakhein) aur roz ek line mein likhne dijiye ki kya dikha.
3 sawaal
- Jang lagne ke liye loha ko kya chahiye?
Jawab dekho
Oxygen aur paani. Loha oxygen aur paani se milkar jang banata hai.
- Teen katori ke prayog mein sabse jaldi jang kahan lagne ki ummeed hai?
Jawab dekho
Namak ghule paani mein rakhi keel. Namak jang ko tez karta hai, aur paani-oxygen dono maujood hain.
- Loha ko jang se bachane ka tareeka kya hai?
Jawab dekho
Us par rang ya tel lagana. Rang ya tel loha ko paani aur hawa se alag rakhte hain.
NCERT se jodo: NCF Preparatory Stage — padarth aur unke badlav (jang lagna)