Class 6 Science · Chapter 9
Short answer:
Is chapter me hum sikhenge ki mixtures ko unke physical properties (size, weight, solubility, magnetic nature) ke basis par kaise alag kiya jaata hai — jaise handpicking, winnowing, sieving, sedimentation, filtration, evaporation, condensation aur churning.
Rasoi me chawal saaf karte waqt, khet me fasal katne ke baad, ya muddy paani ko saaf pine layak banate waqt — hum roz "separation of mixtures" ka use karte hain, chahe humein pata ho ya na ho. Ye chapter sikhata hai ki do ya do se zyada cheezein mix hone par unhe wapas kaise alag kiya jaaye, bina koi naya padarth (substance) banaye — kyunki mixture me har component apni original properties nahi khota. Hum sikhenge handpicking, threshing, winnowing, sieving, sedimentation, decantation, filtration, evaporation, condensation, churning, aur magnetic separation jaise methods, aur ye samjhenge ki kaunsi method kab use karni hai — ye depend karta hai particles ke size, weight, solubility, aur magnetic properties par.
Chapter 9 Summary — 5 Minute Revision
Do ya zyada padarthon ke mix hone se mixture banta hai, aur unhe wapas alag karne ke process ko separation kehte hain. Har method particles ki kisi khaas property par based hai: handpicking (dikhne ka fark), threshing/winnowing (weight aur hawa), sieving (size), sedimentation/decantation (gravity se heavy solid baithna), filtration (porous material se undissolved solid rokna), evaporation/condensation (liquid-solid ya liquid-vapour badalna), churning (density fark) aur magnetic separation (magnetic property). Real life mein aksar ek se zyada methods ek saath use hoti hain — jaise muddy paani saaf karne ke liye sedimentation, decantation, aur filtration teeno.
In-Text Questions — Solutions
Chai banate waqt chai-patti ko chai se alag karne ke liye kaunsi method use hoti hai?
Filtration — chalni ya strainer se chai ko chhaana jaata hai jisse chai-patti (undissolved solid) rah jaati hai aur liquid chai neeche nikal jaati hai.Ek kisan ke paas gehun aur chhoti pathhar (kankad) ka mixture hai, thodi si matra me. Woh kaunsi method use karega?
Handpicking — kyunki kankad size/color me gehun se alag dikhte hain aur matra kam hai, unhe haath se chun kar alag kiya ja sakta hai.Muddy (gandla) paani ko turant peene layak kyu nahi bana sakte sirf sedimentation se?
Sedimentation sirf heavy mitti particles ko neeche baithata hai, lekin bahut chhote suspended particles aur germs paani me reh jaate hain — poori tarah saaf karne ke liye filtration aur purification bhi zaroori hai.Exercise Questions — Solutions (Q1–Q4)
Kheton se katी hui fasal me anaj ke dane bhoosi (husk) se mile hote hain. Kisan inhe kaise alag karta hai jab hawa chal rahi ho?
Kisan winnowing (ओसाना) ka use karta hai — anaj-bhoosi mix ko upar se gira kar hawa me chodte hain. Bhaari anaj dane seedhe neeche gir jaate hain, halki bhoosi hawa ke saath door udd jaati hai. Isme hawa ka behna zaroori hai, warna separation nahi hoga.Ek gilaas paani me chini (sugar) daal kar mix kiya. Kya is mixture ko filtration se alag kiya ja sakta hai? Reason do.
Nahi. Chini paani me ghul (dissolve) jaati hai aur solution bana leti hai — chini ke particles itne chhote ho jaate hain ki filter paper ke chhidron (pores) se aasani se nikal jaate hain. Filtration sirf undissolved (insoluble) solid ko liquid se alag karta hai. Yahan sahi method hai evaporation — paani ko garam karke udaa diya jaaye, chini bartan me reh jaayegi.Namak aur paani ke mixture (khara paani) se shudh (pure) paani wapas kaise hasil karoge?
Condensation ke through — paani ko garam karke bhaap (vapour) banaya jaata hai, phir us bhaap ko thanda karke wapas paani (liquid) me badla jaata hai. Ye process distillation kehlaata hai jisme evaporation + condensation dono ka use hota hai. Namak bartan me piche reh jaata hai.Do bacchon ke beech behas ho rahi hai — ek kehta hai sabhi mixtures ko haath se chhaant (handpick) kar alag kiya ja sakta hai, doosra na maanta hai. Kaun sahi hai aur kyun?
Doosra bachcha sahi hai. Handpicking sirf tab kaam karti hai jab mixture me particles size, shape, color ya texture me alag-alag dikhte hon aur unki matra kam ho — jaise chawal me kankad (chhoti pathhar). Lekin agar mixture solution hai (jaise namak-paani) ya particles bahut chhote/mile hue hain, toh haath se chunna possible nahi — us case me evaporation, filtration, ya condensation jaisi method use hoti hai.Important Equations — Ek Nazar Me
| Method | Kab use hoti hai | Example |
|---|---|---|
| Handpicking | Bade, alag-dikhne wale particles, kam matra | Chawal se kankad chunna |
| Threshing | Anaj ko stalks/bhoosi se alag karna | Gehun ki katai ke baad |
| Winnowing | Bhaari aur halke solid particles (hawa ki madad se) | Anaj se bhoosi udaana |
| Sieving | Alag size ke particles | Aate ko chalni se chalna |
| Sedimentation | Insoluble heavy solid, liquid me | Muddy paani me mitti baithna |
| Decantation | Sedimentation ke baad upar ka clear liquid alag karna | Baithe hue mitti se paani nitharna |
| Filtration | Undissolved solid ko liquid se alag karna | Chai ki patti chhaanna |
| Evaporation | Solid ko solution se wapas paane ke liye (liquid udaao) | Namak ke paani se namak |
| Condensation | Vapour ko wapas liquid banana | Distillation me pure paani |
| Churning | Density ke fark se semi-solid ko alag karna | Doodh se makhan |
| Magnetic separation | Magnetic aur non-magnetic solids | Iron filings aur sulphur |
↔ Table ko side me swipe karein
Common Mistakes — Yahan Marks Kat te Hain
- Filtration aur sedimentation ko same samajhna — dono alag processes hain; filtration me porous material use hota hai, sedimentation me sirf gravity.
- Sochna ki dissolved substance (jaise chini/namak paani me) ko filtration se alag kiya ja sakta hai — asal me ye solution ban jaata hai aur filter paper se nikal jaata hai, evaporation hi sahi tareeka hai.
- Threshing aur winnowing ka order ulta samajhna — pehle threshing (dana bhoosi se alag), phir winnowing (halki bhoosi hawa se udaana).
- Decantation ko filtration ka substitute maan lena — decantation sirf tab kaam karta hai jab solid neeche baith chuka ho (sedimentation ke baad), fine particles ke liye filtration zaroori hai.
- Evaporation aur condensation ko same process samajhna — evaporation me liquid vapour banta hai (garmi se), condensation me vapour wapas liquid banta hai (thanda hone se) — dono opposite hain.
- Ye maan lena ki sirf ek method se koi bhi mixture separate ho jaayega — real mixtures (jaise muddy paani) ko aksar sedimentation + decantation + filtration jaisi multiple methods combine karke separate karna padta hai.
Board-Style Important Questions
- Winnowing ka use kis prakar ke mixture ko alag karne ke liye kiya jaata hai? Ek example ke saath samjhaiye.
- Sedimentation aur decantation me antar spasht kijiye. Muddy paani ko saaf karne ke process ko step-by-step likhiye.
- Namak ke ghol (salt solution) se shudh namak wapas kaise praapt karenge? Process ka naam bataate hue steps likhiye.
- Kisi bhi do separation methods ka naam likhiye jinme 'physical properties' ka use hota hai, aur unke examples dijiye.
Aksar Poochhe Jaane Wale Sawaal
Filtration aur sedimentation me kya fark hai?
Sedimentation me heavy insoluble particles apne aap gravity ki wajah se bartan ke neeche baith jaate hain (jaise muddy paani ko kuch der rakhne par mitti neeche baith jaati hai). Filtration me hum ek filter paper ya cheezcloth jaisi porous cheez use karte hain jisse liquid toh nikal jaaye lekin solid particles fas jaayein. Aksar sedimentation ke baad decantation aur phir filtration together use hoti hai clear paani paane ke liye.
Kya sabhi mixtures ko separate kiya ja sakta hai?
Haan, theoretically har mixture ko uske physical properties (size, density, solubility, magnetic nature, boiling point) ke basis par alag kiya ja sakta hai. Method ka chunav is baat par depend karta hai ki mixture ke components kis tarah ke hain — solid-solid, solid-liquid, ya liquid-liquid.
Churning (bilona) ka use kahan hota hai?
Churning ka use doodh se makhan (butter/cream) nikalne me hota hai — dahi ya doodh ko tezi se ghumaya (agitate) jaata hai jisse fat ke particles aapas me jud kar upar aa jaate hain, aur baaki matter (chhaach) niche reh jaata hai. Ye ek mechanical separation method hai jo density ke fark par based hai.
Magnetic separation kis tarah ke mixture ke liye use hoti hai?
Jab mixture me ek component magnetic ho (jaise iron filings) aur doosra non-magnetic ho (jaise sulphur powder ya mitti), tab ek magnet ka use karke magnetic particles ko khींच kar alag kiya jaata hai. Ye industries me scrap metal alag karne ke liye bhi use hoti hai.
Threshing aur winnowing me kya order hota hai?
Pehle threshing hoti hai — fasal ki bundle ko peet kar ya machine se anaj ke dano ko bhoosi (stalks) se alag kiya jaata hai. Uske baad winnowing hoti hai jisme hawa ki madad se halki bhoosi ko anaj ke bhaari dano se alag kiya jaata hai.
Kya ek mixture ko separate karne ke liye ek se zyada method use ho sakti hai?
Haan, bilkul. Jaise muddy paani ko saaf karne ke liye pehle sedimentation, phir decantation, aur agar aur bhi saaf chahiye toh filtration — teeno methods ek ke baad ek use hoti hain. Real-life mixtures aksar complex hote hain isliye combination of methods common hai.
Class 6 Science — Saare Chapters
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