Minerals | Class 8 Science Ch 8 (Nature of Matter)

Class 8 · Science (Curiosity)Ch 8 · Nature of MatterPost 8 / 9⏱ 15–18 min

Minerals (Khanij)

Patthar ke andar chhupe asli khiladi: quartz, mica, calcite, talc… aur kabhi-kabhi shuddh sona bhi! 💎🪨

A · Shuruaat

📖 Kahani: Naale ke Kinare Khazana

Gaon ke do bachche pahadi naale ke kinare rang-birange patthar aur crystal haath mein le kar dhyaan se dekh rahe hain
Naale ke kinare mile chamakte patthar aur crystal. Yeh sab kya hain? (Image: Canva AI se banayi gayi · © charumam.com)

Diwali ki chhuttiyon mein Golu aur Priya naani ke gaon gaye. Gaon ke paas ek pahadi naala tha. Wahan patthar beente-beente Golu ko ek bilkul paardarshi, nukeela crystal mila, kaanch jaisa!

Priya ko ek patthar mila jiski patli-patli chamakdaar parten nail se nikal rahi thi, jaise kitaab ke panne. Aur ek chhota, bhaari, sunahra sa tukda bhi.

Golu uchhal pada: “Sona! Hum ameer ho gaye!”

Tabhi Rohan ka video call aaya. Usne hans kar kaha: “Pehle pakka karo. Har chamakne wali cheez sona nahi hoti! Waise yeh sab ke sab minerals ho sakte hain.”

Priya ne poochha: “Mineral? Woh toh paani ki bottle par likha hota hai na, ‘mineral water’?”

Aaj hum yahi samjhenge: mineral asal mein kya hai, patthar (rock) se kaise alag hai, aur yeh element hai, compound hai ya mixture? 🔍

— 📌 charumam.com

🎯 Is Post Mein Kya Seekhenge

  • Mineral ki paribhasha: prakritik, thos, aur fixed chemical banaavat wala padarth
  • Zyadatar minerals compound kyun hain, aur kuch minerals shuddh element kyun (jaise sona, tamba, sulfur)
  • Rock (chattaan) aur mineral ka farq: rock aksar minerals ka mixture hoti hai
  • Quartz, calcite, mica, talc, olivine, pyroxene jaise minerals aur unki pehchaan
  • Minerals ka upyog: cement, talcum powder, kaanch, metals (ores) aur gehne
— 📌 charumam.com

🧱 Basics: Pehle Yeh Aana Chahiye

1. Pure substance: jisme ek hi tarah ke kan hon, aur jiski banaavat har jagah same ho. (Post 3: Pure Substance Kya Hai?)

2. Element: sabse saral pure padarth, jaise sona (Au), tamba (Cu), sulfur (S). (Post 4: Elements)

3. Compound: do ya zyada elements ka fixed anupaat mein chemical jod, jaise namak (NaCl). (Post 5: Compounds)

4. Mixture: padarth bas mile hue, anupaat kuch bhi. (Post 1: Mixture Kya Hai?)

5. Prakritik (natural): jo dharti par apne aap bana ho, insaan ne factory mein na banaya ho.

— 📌 charumam.com
B · Samjho

💡 Concept: Mineral Kya Hai?

1️⃣ Paribhasha: teen sharten

Koi padarth mineral tab kehlaata hai jab woh:
✅ Prakritik (natural) ho: dharti par apne aap bana ho,
✅ Thos (solid) ho,
✅ Uski chemical banaavat fixed ho: har tukde mein wahi elements, wahi anupaat.
Teesri shart hi sabse khaas hai. Fixed banaavat ka matlab hai ki mineral ek pure substance hai, mixture nahi.

2️⃣ Zyadatar minerals compound hain

  • Quartz = silicon + oxygen ka compound (silicon dioxide, SiO₂). Nadi aur samudra ki ret ka zyadatar hissa quartz ke kan hote hain.
  • Calcite = calcium, carbon aur oxygen ka compound (calcium carbonate, CaCO₃). Chuna-patthar (limestone) aur sangmarmar (marble) mainly calcite se bane hain.
  • Halite = sodium chloride (NaCl), yaani prakritik namak ka mineral. Sendha namak isi ka roop hai.
  • Mica, talc, olivine, pyroxene bhi compounds hain. Inme silicon aur oxygen ke saath aur elements jude hain (jaise magnesium, iron, aluminium).

3️⃣ Kuch minerals shuddh element hain (native minerals)

  • Metals: sona (gold), chaandi (silver), tamba (copper) kabhi-kabhi dharti mein shuddh roop mein milte hain.
  • Non-metals: sulfur (gandhak) aur carbon (heera aur graphite ke roop mein) bhi shuddh roop mein milte hain.
  • Aise minerals bahut kam hain. Isliye niyam yaad rakho: minerals zyadatar compound, kabhi-kabhi element.

4️⃣ Rock (chattaan) = minerals ka mixture

Zyadatar rocks kai minerals ka mixture hoti hain. Jaise granite (rasoi ke platform wala chitkabra patthar) mein quartz (safed/paardarshi), feldspar (gulaabi ya safed) aur mica (kaale chamakte daane) mile hote hain. Har mineral apna rang aur gun rakhta hai, aur unka anupaat ek patthar se doosre mein badal jaata hai.
Isliye granite ke har slab ka design alag dikhta hai. Fixed banaavat nahi, toh mixture!

Kuch minerals ke daane aankh se dikh jaate hain, kuch ke liye magnifying glass ya microscope chahiye.

5️⃣ Minerals hamare kis kaam ke?

  • Cement: calcite, quartz, alumina aur iron oxide se banta hai, jo minerals hain ya minerals se milte hain.
  • Talcum powder: talc mineral ko peeskar banta hai. Talc itna naram hai ki nakhoon se bhi khurach jaata hai.
  • Kaanch: ret (quartz) ko soda aur chuna-patthar ke saath pighla kar banta hai.
  • Metals: loha, aluminium, tamba jaise metals minerals se nikaale jaate hain. Jis mineral (ya chattaan) se metal faayde ke saath nikle, use ore (ayask) kehte hain, jaise loha ka ore haematite.
  • Bijli ka insulation: mica garmi sehta hai aur bijli nahi chalata, isliye iron (press) aur heater mein kaam aata hai.

Toh kahani ka jawab: Golu ka paardarshi crystal shayad quartz hai, Priya ki parton wali cheez mica. Aur sunahra tukda? Woh sona bhi ho sakta hai, ya “nakli sona” pyrite! Jaanch ke bina kuch pakka nahi.

— 📌 charumam.com

📷 Asli Minerals ki Photos

Paardarshi quartz crystals ka guchha
QuartzCompound (SiO₂)
Photo: JJ Harrison, CC BY-SA 2.5, resized, via Wikimedia Commons · licence
Chamakdaar parton wala mica (abhrak) mineral
Mica (abhrak)Compound, parton mein toot-ta hai
Photo: James St. John, CC BY 2.0, resized, via Wikimedia Commons · licence
Calcite mineral ka crystal
CalciteCompound (CaCO₃)
Photo: Nessa Eull, CC0, via Wikimedia Commons
Talc mineral ka safed-hara naram tukda
TalcCompound, sabse naram mineral
Photo: Public domain, via Wikimedia Commons
Prakritik sone ka chhota dhela (gold nugget)
Sona (native gold)Element (Au)
Photo: James St. John, CC BY 2.0, resized, via Wikimedia Commons · licence
Peela sulfur (gandhak) mineral
Sulfur (gandhak)Element (S), non-metal
Photo: Ben Mills, Public domain, via Wikimedia Commons

Upar ki chaar photos compound minerals ki hain, neeche ki do native (element) minerals ki. Dhyaan do: compound wale zyada hain, bilkul asli duniya ki tarah!

— 📌 charumam.com

🖼️ Diagrams: Picture se Samjho

Rock (granite) = minerals ka MIXTURE Quartz (safed/paardarshi) Feldspar (gulaabi/safed) Mica (kaale, chamakdaar) Har daana ek mineral (pure substance) Poori chattaan = mixture Anupaat har patthar mein alag © charumam.com
Diagram 1: Granite ko paas se dekho toh teen tarah ke daane dikhte hain. Har daana ek mineral hai; sab mil kar chattaan.
MINERAL prakritik · thos · fixed banaavat ZYADATAR: COMPOUND KABHI-KABHI: ELEMENT • Quartz (SiO₂)• Calcite (CaCO₃)• Halite / sendha namak (NaCl)• Mica, Talc• Olivine, Pyroxene• Haematite (loha ka ore) Metals:• Sona (Au), Chaandi (Ag)• Tamba (Cu)Non-metals:• Sulfur (S)• Carbon: heera, graphite © charumam.com
Diagram 2: Mineral hamesha pure substance hai. Zyadatar compound, kuch native element.
Kathorta ki seedhi (Mohs scale, 1 se 10) 1 2 3 4 5 6 7 8 9 10 TalcCalciteQuartzHeera nakhoon ~2.5tambe ka sikka ~3.5kaanch / steel ki chaaku ~5.5 Bade number wala chhote number wale ko khurach sakta hai, chhota bade ko nahi. © charumam.com
Diagram 3: Minerals ki ek pehchaan unki kathorta (hardness) hai. Talc sabse naram (1), heera sabse sakht (10). Ghar ki cheezon ke number lagbhag hain.
— 📌 charumam.com

🔐 Deep Concept: Fixed Banaavat ka Asli Matlab

1. Sona: mineral bhi, metal bhi! Dharti mein mila shuddh sona prakritik hai, thos hai, aur uski banaavat fixed hai (sirf gold atom, Au). Isliye woh mineral hai. Saath hi woh ek element hai jo chamakta hai, peet kar patla ho jaata hai aur bijli chalata hai, yaani ek metal. Ek hi cheez, do pehchaan: “mineral” batata hai ki woh kahan se aur kaise mila, “metal” batata hai ki uske gun kaise hain.

2. Heera aur graphite: ek element, do mineral. Dono sirf carbon atom se bane hain, par atom alag tarah se jude hain. Heera sabse sakht prakritik padarth hai, jabki graphite itna naram hai ki pencil ki “lead” mein use hota hai. Kyun? Gun sirf atom se nahi, atom ki jamavat (arrangement) se bhi tay hote hain.

3. Rock fixed kyun nahi? Granite ke ek tukde mein quartz zyada ho sakta hai, doosre mein feldspar. Koi ek formula nahi likh sakte. Isliye rock mixture hai, jabki uska har mineral daana pure substance hai.

4. Sach aur “nakli sona”. Pyrite (iron aur sulfur ka compound) sunahra chamakta hai, isliye ise “fool’s gold” kehte hain. Asli sona bahut bhaari aur naram hota hai, aur khurachne par sunahri lakeer deta hai; pyrite kathor hai aur khurachne par kaali-hari si lakeer deta hai.

Yaad rakhne ka formula:
Mineral = Prakritik + Thos + Fixed banaavat
Rock = kai minerals ka mixture
Ore = woh mineral/rock jisse metal faayde ke saath nikle

5. Mineral water ka “mineral”. Bottle wale paani mein bahut thodi matra mein ghule hue padarth (jaise calcium, magnesium ke compounds) hote hain, jo chattaanon se aaye. Par paani khud mineral nahi, aur woh bottle ka paani ek mixture (solution) hai. Rozmarra ka shabd aur science ka shabd hamesha ek matlab nahi rakhte!

— 📌 charumam.com

✏️ Examples: Mineral, Pehchaan aur Kaam

MineralElement ya compound?Pehchaan / kaam
QuartzCompound (SiO₂)Paardarshi ya safed, kathor (7); ret aur kaanch
CalciteCompound (CaCO₃)Chuna-patthar aur sangmarmar mein; cement
Mica (abhrak)CompoundPatli chamakdaar parten; bijli ka insulation
TalcCompoundSabse naram (1), chikna; talcum powder
Olivine, PyroxeneCompoundHare-kaale daane, jwalamukhi (volcanic) chattaanon mein
HaliteCompound (NaCl)Sendha namak; khaane mein
HaematiteCompound (iron + oxygen)Laal-bhoora; loha ka mukhya ore
Sona (native gold)Element (Au)Sunahra, bhaari, naram; gehne
Tamba (native copper)Element (Cu)Laal-bhoora metal; kabhi shuddh roop mein milta hai
Sulfur (gandhak)Element (S)Peela, non-metal
Heera / GraphiteElement (C)Heera sabse sakht (10); graphite pencil mein
— 📌 charumam.com

⚖️ Difference Table: Mineral vs Rock

BaatMineralRock (chattaan)
Kya hai?Pure substanceAksar mixture (kai minerals ka)
Chemical banaavatFixedFixed nahi; jagah-jagah badalti hai
FormulaLikh sakte hain (SiO₂, CaCO₃, Au)Ek formula nahi
Element/compound/mixtureZyadatar compound, kabhi elementMixture
UdaharanQuartz, calcite, mica, talc, sonaGranite, chuna-patthar, sangmarmar, basalt
Dikhne meinEk jaisa rang aur bunaavatAlag-alag rang ke daane (jaise granite)
— 📌 charumam.com

🚫 Misconceptions: Log aisa sochte hain… lekin

❌ “Mineral aur rock ek hi cheez hain.”
✅ Mineral pure substance hai (fixed banaavat); rock aksar kai minerals ka mixture hai.
❌ “Saare minerals elements hain.”
✅ Zyadatar minerals compound hain (quartz, calcite). Sona, tamba, sulfur jaise kuch hi native elements hain.
❌ “Mineral water ka paani ek mineral hai.”
✅ Usme minerals se aaye padarth thodi matra mein ghule hain. Paani ek mixture (solution) hai, mineral nahi.
❌ “Jo cheez sunahri chamke, woh sona hai.”
✅ Pyrite bhi sunahra chamakta hai. Pehchaan ke liye vazan, kathorta aur khurachne ki lakeer dekhni padti hai.
❌ “Fixed banaavat hai toh woh lab mein bana hoga.”
✅ Mineral prakritik hota hai. Lab mein bana crystal (jaise lab-grown heera) mineral nahi maana jaata, chahe banaavat same ho.
❌ “Heera aur graphite alag elements hain.”
✅ Dono sirf carbon hain; atom ki jamavat alag hai, isliye gun alag.
— 📌 charumam.com

🔤 Key Terms (Exam mein English shabd hi likhna)

Mineral: khanij; prakritik, thos, fixed banaavat wala padarth
Rock: chattaan; aksar minerals ka mixture
Native mineral: jo shuddh element ke roop mein mile (sona, sulfur)
Ore: ayask; jisse metal faayde ke saath nikle
Quartz: silicon dioxide (SiO₂), ret ka mukhya hissa
Calcite: calcium carbonate (CaCO₃)
Mica: abhrak; parton mein khulne wala mineral
Talc: sabse naram mineral; talcum powder
Hardness: kathorta; khurach-test se naapte hain
Mohs scale: 1 (talc) se 10 (heera) tak kathorta ki seedhi
Crystal: niyamit (regular) aakaar wala thos
Fixed composition: tay banaavat; har jagah wahi anupaat
— 📌 charumam.com

❓ FAQs

Kya koyla (coal) mineral hai?

Science ki sakht paribhasha mein nahi. Koyla paudhon ke avshesh se bana hai aur uski banaavat fixed nahi, isliye geologist use mineral nahi, ek chattaan (rock) maante hain. Rozmarra aur sarkaari bhasha mein “mineral resources” mein koyla gina jaata hai, par yeh alag baat hai.

Kya barf mineral hai?

Glacier ki prakritik barf mineral ki shartein poori karti hai: prakritik, thos, fixed banaavat (H₂O). Par fridge ki barf insaan ne banayi hai, isliye use mineral nahi kehte. Mazedaar na?

Ret mein chamakte daane kya hote hain?

Zyadatar quartz ke kan, aur kabhi-kabhi mica ke chhote chamakdaar tukde. Magnifying glass se dekhoge toh alag-alag daane dikhenge, yaani ret bhi ek mixture hai.

Bharat mein kaun se minerals milte hain?

Bharat mein loha ka ore, bauxite (aluminium ke liye), chuna-patthar, mica aur kai doosre minerals milte hain. Jharkhand ka Koderma ilaaka mica ke liye mashhoor raha hai, aur Rajasthan ka Makrana sangmarmar ke liye.

Mineral ki pehchaan kaise karte hain?

Rang, chamak, kathorta (khurach-test), khurachne par lakeer ka rang (streak), vazan aur todne par kaise tootta hai (jaise mica parton mein), in sab ko mila kar.

— 📌 charumam.com
C · Karke Dekho

🧪 Activity: Patthar Jaasoos (Rock aur Mineral Pehchaano)

NCERT book ke minerals wale hisse mein koi alag numbered activity nahi hai, par chapter kehta hai ki minerals ke daane aankh, magnifying glass ya microscope se dekhe ja sakte hain. Isi soch par ek aasaan activity hum apne shabdon mein step-by-step karenge.

Saamaan: 4–5 alag patthar (gali, park ya naale se), thodi ret, ek magnifying glass (na ho toh mobile camera ka zoom), safed kaagaz, notebook.

Saaf karo: pattharon ko paani se dho kar sukha lo, taaki mitti hat jaaye aur asli rang dikhe.
Dhyaan se dekho: har patthar ko magnifying glass se dekho. Kya usme alag-alag rang ke daane hain (safed, kaale, gulaabi)? Ya poora patthar ek jaisa hai?
Table banao: notebook mein likho: patthar ka number, kitne tarah ke daane dikhe, unka rang aur chamak.
Ret ki jaanch: safed kaagaz par chutki bhar ret phailao aur dekho. Paardarshi/safed daane (quartz), chamakdaar patle tukde (mica) aur kaale daane alag-alag ginne ki koshish karo.
Nateeja likho: jis patthar mein kai tarah ke daane hain, use “rock = minerals ka mixture” likho. Har tarah ka daana ek mineral hai.
👀 Aksar kya nateeja aata hai aur kyun? (Click karo)
Kya dekhaMatlab
Zyadatar pattharon mein 2–3 tarah ke daaneRock kai minerals ka mixture hai
Ret mein paardarshi daane sabse zyadaRet mein quartz sabse zyada hota hai, kyunki woh kathor hai aur aasaani se ghista nahi
Kuch chamakdaar patle tukdeShayad mica
Koi-koi patthar ek jaisa (jaise safed sangmarmar ka tukda)Usme lagbhag ek hi mineral (calcite) zyada hai

Is activity se kya seekha? Patthar ko paas se dekho toh woh kai minerals ka mixture nikalta hai, aur har mineral daana apna rang aur chamak rakhta hai.

Yeh activity NCERT ki Class 8 Science book Curiosity (Chapter 8) par aadharit hai, aur yahan apne shabdon mein samjhayi gayi hai.

— 📌 charumam.com

🏠 Mini Experiments (Ghar pe)

Experiment 1: Sendha namak ka crystal
Rasoi se sendha namak ka ek bada daana lo aur magnifying glass se dekho. Kinare seedhe aur kone lagbhag 90° ke dikhte hain?
Ek chammach paani mein ek chhota daana daal kar hilao.

Result: daana aksar dibbe (cube) jaisa toot-ta hai, aur paani mein ghul jaata hai. Yeh halite mineral (NaCl) hai, ek compound. Uska niyamit aakaar uski fixed banaavat ki nishaani hai.

Experiment 2: Talcum powder ka chiknaapan
Hatheli par chutki bhar talcum powder lo aur ungliyon ke beech ragdo.
Ab chutki bhar ret ragdo (dhyaan se, halke haath se) aur farq mehsoos karo.

Result: talc bahut chikna aur naram lagta hai, ret khurdari. Talc sabse naram mineral (1) hai, aur ret ka quartz bahut kathor (7). Mineral ki pehchaan mein kathorta kaam aati hai!

Experiment 3: Nakhoon ka khurach-test
Apne nakhoon se ek chalk, ek sendha namak ka daana aur ek chhota kankad (gali ka patthar) khurachne ki koshish karo.
Likho: kis par nishaan bana, kis par nahi.

Result: chalk par aasaani se nishaan, namak par mushkil se, kankad par aksar nahi. Nakhoon ki kathorta lagbhag 2.5 hai: isse naram cheez khurach jaati hai, sakht nahi.

— 📌 charumam.com

⚠️ Safety Notes

Naale, nadi ya khadaan (mine) ke paas akele mat jaao; kisi bade ke saath hi patthar ikattha karo. Pattharon ko hathode se todne ki koshish mat karo, tukde aankh mein ja sakte hain.
Talcum powder ko naak ke paas mat udaao aur sunghna nahi. Ret ko halke haath se ragdo aur aankhon se door rakho. Experiment ka namak khaana nahi. Kaam ke baad haath dhona.

🧠 Think Like a Scientist

Observe (dekho): Priya ne dekha ki naale ki ret mein kuch daane paardarshi aur chamakdaar hain, aur kuch kaale.
Guess (andaza): “Shayad yeh alag-alag minerals hain, aur paardarshi wale kaanch jaise kathor quartz hain.”
Test (jaanch): Usne ek purani, bekaar kaanch ki botal ke tukde par (bade ki nigraani mein) paardarshi daane ko ragda, aur doosri taraf ek chalk ko ragda.
Result (nateeja): Paardarshi daane ne kaanch par halki kharonch bana di; chalk ne nahi, ulta chalk khud ghis gaya.
Conclusion (nishkarsh): Paardarshi daana kaanch (~5.5) se sakht hai, jo quartz (7) ke saath mel khaata hai. Ret alag-alag minerals ka mixture hai, aur kathorta se mineral pehchaan sakte hain.
— 📌 charumam.com

🌍 Real Life Mein Minerals

  • Ghar banana: cement (calcite, quartz aur doosre minerals se), ret (quartz), aur granite-marble ke farsh.
  • Rasoi: sendha namak (halite), aur kaanch ke bartan (quartz wali ret se bane).
  • Bathroom: talcum powder (talc).
  • Bijli ke saaman: press aur heater mein mica; taaron ka tamba aur mobile ke metals minerals/ores se nikalte hain.
  • Gehne: sona, chaandi, aur heera jaise ratna, sab minerals se.
  • Itihaas: Taj Mahal Rajasthan ke Makrana sangmarmar se bana hai, jo mainly calcite mineral ka bana patthar hai.
— 📌 charumam.com
D · Revise

🔁 Recap: Poora Post Ek Nazar Mein

  • Mineral = prakritik + thos + fixed chemical banaavat; isliye mineral ek pure substance hai.
  • Zyadatar minerals compound hain (quartz SiO₂, calcite CaCO₃, halite NaCl, mica, talc, olivine, pyroxene).
  • Kuch minerals native elements hain: sona, chaandi, tamba (metals), sulfur aur carbon (non-metals).
  • Rock aksar kai minerals ka mixture hai, jaise granite = quartz + feldspar + mica.
  • Cement calcite, quartz, alumina, iron oxide se; talcum powder talc se; kaanch quartz wali ret se.
  • Metals minerals se nikalte hain; aise mineral/rock ko ore kehte hain (loha: haematite).
  • Kathorta: talc sabse naram (1), heera sabse sakht (10). Sona mineral bhi hai aur metal bhi.
— 📌 charumam.com
E · Practice

✍️ Fill in the Blanks

1. Mineral prakritik, thos aur ______ chemical banaavat wala padarth hai.

fixed (tay)

2. Zyadatar rocks kai ______ ka mixture hoti hain.

minerals

3. Talcum powder ______ mineral se banta hai.

talc

4. Quartz silicon aur ______ ka compound hai.

oxygen (SiO₂)

5. Sona, chaandi aur tamba kabhi-kabhi dharti mein ______ roop mein milte hain.

shuddh (native/element)

6. Jis mineral se metal faayde ke saath nikaala jaaye, use ______ kehte hain.

ore (ayask)

✅ True / False

1. Saare minerals compound hote hain.

False: zyadatar compound hain, par sona, tamba, sulfur jaise kuch minerals shuddh element hain.

2. Granite ek mineral hai.

False: granite ek rock hai, jo quartz, feldspar aur mica ka mixture hai.

3. Calcite chuna-patthar aur sangmarmar ka mukhya mineral hai.

True: dono mainly calcium carbonate (calcite) se bane hain.

4. Factory mein bana crystal bhi mineral kehlaata hai, agar uski banaavat fixed ho.

False: mineral prakritik hona chahiye; lab ya factory mein bani cheez mineral nahi maani jaati.

5. Talc sabse naram mineral hai.

True: Mohs scale par talc 1 hai; nakhoon se bhi khurach jaata hai.

6. Mineral ki chemical banaavat har tukde mein badalti rehti hai.

False: mineral ki banaavat fixed hoti hai; badalti banaavat rock (mixture) ki pehchaan hai.

🔘 MCQs

Q1. Inme se kaun sa mineral ki shart NAHI hai? (a) Prakritik hona (b) Thos hona (c) Fixed banaavat (d) Paani mein ghulna

✅ (d) Paani mein ghulna: zyadatar minerals (jaise quartz) paani mein nahi ghulte; yeh shart nahi hai.
(a), (b), (c) teeno mineral ki asli shartein hain.

Q2. Inme se kaun sa mineral ek element hai? (a) Quartz (b) Calcite (c) Sulfur (d) Talc

✅ (c) Sulfur: native non-metal element (S).
(a) quartz compound hai (SiO₂).
(b) calcite compound hai (CaCO₃).
(d) talc bhi compound hai.

Q3. Granite kya hai? (a) Element (b) Compound (c) Ek mineral (d) Minerals ka mixture (rock)

✅ (d): granite mein quartz, feldspar, mica mile hain.
(a) element nahi, kai padarth hain.
(b) compound nahi, koi fixed formula nahi.
(c) mineral nahi, kyunki banaavat fixed nahi.

Q4. Talcum powder kis mineral se banta hai? (a) Mica (b) Talc (c) Quartz (d) Olivine

✅ (b) Talc: talc ko peeskar.
(a) mica insulation mein kaam aata hai.
(c) quartz se ret aur kaanch.
(d) olivine jwalamukhi chattaanon ka mineral hai, powder ke liye nahi.

Q5. Zyadatar minerals kya hote hain? (a) Mixtures (b) Compounds (c) Gas (d) Liquid

✅ (b) Compounds: jaise quartz, calcite.
(a) mixture nahi, mineral ki banaavat fixed hai.
(c) aur (d) galat, mineral thos hota hai.

Q6. Cement banane mein inme se kaun sa mineral lagta hai? (a) Talc (b) Calcite (c) Sona (d) Sulfur

✅ (b) Calcite: calcite, quartz, alumina, iron oxide se cement banta hai.
(a) talc powder ke liye.
(c) sona gehnon ke liye.
(d) sulfur cement ka mukhya hissa nahi.

Q7. Heera aur graphite dono kis element se bane hain? (a) Silicon (b) Carbon (c) Calcium (d) Sulfur

✅ (b) Carbon: dono sirf carbon atom; jamavat alag.
(a) silicon quartz mein hai.
(c) calcium calcite mein hai.
(d) sulfur alag peela element hai.

Q8. Ret ka zyadatar hissa kis mineral ka hota hai? (a) Quartz (b) Talc (c) Mica (d) Halite

✅ (a) Quartz: kathor hai, aasaani se nahi ghista, isliye ret mein bacha rehta hai.
(b) talc bahut naram, jaldi ghis jaata hai.
(c) mica thoda milta hai, zyadatar nahi.
(d) halite paani mein ghul jaata hai.

🔗 Assertion–Reason

Options: (a) A aur R dono sahi, aur R, A ko samjhata hai · (b) A aur R dono sahi, par R, A ko nahi samjhata · (c) A sahi, R galat · (d) A galat, R sahi

1. A: Granite ek rock hai, mineral nahi. R: Granite mein kai minerals bina fixed anupaat ke mile hote hain.

✅ (a): fixed banaavat na hona hi granite ko mineral ke bajaay rock (mixture) banata hai. R seedha A ko samjhata hai.

2. A: Sona ek mineral bhi hai aur metal bhi. R: Sona gehne banane mein use hota hai.

✅ (b): dono sahi, par gehnon mein use hona yeh nahi samjhata ki sona mineral aur metal kyun hai. Asli wajah: woh prakritik, thos, fixed banaavat wala hai (mineral) aur metal ke gun rakhta hai.

3. A: Saare minerals compound hote hain. R: Quartz silicon aur oxygen ka compound hai.

✅ (d): A galat, kyunki sona, sulfur jaise native minerals element hain. R sahi hai.

📝 Very Short Answer (1 mark)

1. Mineral ki ek line mein paribhasha likho.

Mineral prakritik, thos padarth hai jiski chemical banaavat fixed hoti hai.

2. Do aise minerals ke naam likho jo element hain.

Sona (gold) aur sulfur. (Tamba, chaandi, heera bhi sahi.)

3. Calcite ka chemical naam likho.

Calcium carbonate (CaCO₃).

4. Granite mein milne wale teen minerals batao.

Quartz, feldspar, mica.

5. Loha ke mukhya ore ka naam likho.

Haematite.

🗒️ Short Answer (2–3 marks)

1. Mineral aur rock mein do farq likho.

(i) Mineral pure substance hai jiski banaavat fixed hai; rock aksar kai minerals ka mixture hai jiski banaavat badalti hai. (ii) Mineral ka formula likh sakte hain (jaise SiO₂); rock ka koi ek formula nahi hota.

2. “Minerals zyadatar compound hote hain, par hamesha nahi.” Udaharan se samjhao.

Quartz (SiO₂), calcite (CaCO₃), halite (NaCl) jaise zyadatar minerals mein do ya zyada elements fixed anupaat mein jude hain, yaani compound. Par sona, chaandi, tamba, sulfur aur carbon (heera) kabhi-kabhi shuddh roop mein milte hain; yeh native minerals element hain.

3. Minerals ke teen upyog likho.

(i) Calcite aur quartz se cement. (ii) Talc se talcum powder. (iii) Ores se metal, jaise haematite se loha. (Mica se insulation, quartz wali ret se kaanch bhi sahi.)

4. Lab mein bane heere ko mineral kyun nahi kehte, jabki woh bhi carbon hai?

Mineral ki pehli shart hai prakritik hona. Lab-grown heere ki banaavat prakritik heere jaisi hai, par woh insaan ne banaya hai, dharti ne nahi. Isliye woh mineral nahi kehlaata.

📄 Long Answer (5 marks)

1. Mineral kya hai? Uski teen shartein samjhao, aur batao ki mineral pure substance hai ya mixture. Element aur compound minerals ke do-do udaharan do.

Mineral dharti par prakritik roop se bana thos padarth hai jiski chemical banaavat fixed hoti hai.
Shartein: (1) Prakritik: insaan ne na banaya ho. (2) Thos: liquid ya gas nahi. (3) Fixed banaavat: har tukde mein wahi elements, wahi anupaat.
Pure ya mixture? Fixed banaavat ki wajah se mineral ek pure substance hai, mixture nahi.
Compound minerals: quartz (SiO₂), calcite (CaCO₃).
Element (native) minerals: sona (Au), sulfur (S).
Zyadatar minerals compound hote hain; element wale minerals kam milte hain.

2. “Rock minerals ka mixture hai.” Granite ke udaharan se samjhao, aur batao ki minerals hamari roz ki zindagi mein kaise kaam aate hain.

Granite ko paas se dekhne par teen tarah ke daane dikhte hain: safed/paardarshi quartz, gulaabi ya safed feldspar, aur kaale chamakdaar mica. Har daana ek mineral (pure substance) hai, par poori chattaan mein inka anupaat jagah-jagah badalta hai aur koi ek formula nahi likh sakte. Isliye granite (rock) ek mixture hai.
Roz ki zindagi mein minerals: cement (calcite, quartz, alumina, iron oxide se), talcum powder (talc), kaanch (quartz wali ret), bijli ka insulation (mica), sendha namak (halite), metals (ores se, jaise haematite se loha) aur gehne (sona, chaandi, heera).

📰 Case-Based Question

Rohan ke school ki trip Rajasthan gayi. Ek khadaan (mine) ke paas guide ne teen cheezein dikhayi: (1) ek safed, chikna patthar jise nakhoon se khurachne par safed powder nikalta tha, (2) ek chitkabra patthar jisme safed, gulaabi aur kaale daane the, (3) ek peela, bhurbhura tukda jise guide ne “shuddh gandhak” bataya. Guide ne kaha: “Inme se ek rock hai, do minerals; aur ek mineral toh element bhi hai!”

Q1. Pehli cheez kaun sa mineral ho sakti hai? Kyun?

Talc. Woh bahut naram hai (nakhoon se khurach jaata hai) aur chikna hai; talc sabse naram mineral hai.

Q2. Chitkabra patthar mineral hai ya rock? Kaun se minerals ho sakte hain?

Rock (jaise granite), kyunki usme alag-alag minerals ke daane mile hain: safed quartz, gulaabi feldspar, kaala mica. Yeh mixture hai.

Q3. Kaun sa mineral element bhi hai? Woh metal hai ya non-metal?

Gandhak (sulfur). Yeh native mineral hai, aur ek non-metal element (S).

Q4. Talc ka ek upyog aur sulfur ka rang batao.

Talc se talcum powder banta hai. Sulfur ka rang peela hota hai.

🚀 HOTS (Higher Order Thinking)

1. Nadi ki ret mein quartz bahut zyada aur calcite bahut kam kyun milta hai?

Quartz kathor (7) hai aur paani mein nahi ghulta, isliye pattharon ke tootne-ghisne ke baad bhi bacha rehta hai. Calcite naram (3) hai aur halke acidic paani mein dheere-dheere ghul sakta hai, isliye jaldi ghis kar ya ghul kar kam ho jaata hai.

2. Ek bachcha kehta hai: “Sendha namak aur samudri namak dono NaCl hain, toh dono minerals hain.” Kya woh sahi hai?

Aadha sahi. Sendha namak khadaan se nikla prakritik halite crystal hai, isliye mineral hai. Samudri namak insaan ne samudra ka paani sukha kar banaya hai, aur usme thodi doosri cheezein bhi mili ho sakti hain; dukaan ka namak toh process karke banaya jaata hai. Isliye use mineral nahi kehte, chahe mukhya compound NaCl hi ho.

3. Agar kisi naye patthar ke do tukdon ki jaanch mein ek mein 60% aur doosre mein 30% quartz mile, toh woh patthar mineral hai ya rock? Kyun?

Rock. Banaavat ek tukde se doosre mein badal rahi hai (60% vs 30%), yaani fixed nahi. Mineral ki banaavat har tukde mein same hoti hai.

🏆 Olympiad Corner

1. Mohs scale par ek mineral A, B ko khurach sakta hai, aur B, C ko. Agar C talc hai, toh inme sabse sakht kaun? (a) A (b) B (c) C (d) Kuch nahi keh sakte

✅ (a) A: jo khurachta hai woh sakht hota hai: A > B > C. C (talc) sabse naram.

2. Inme se kaunsa jod sahi hai? (a) Quartz: CaCO₃ (b) Calcite: SiO₂ (c) Halite: NaCl (d) Sona: compound

✅ (c) Halite: NaCl. (a) aur (b) ulte hain: quartz SiO₂, calcite CaCO₃. (d) sona element hai, compound nahi.

3. Ek mineral ke 10 g namune mein 4 g calcium, 1.2 g carbon aur 4.8 g oxygen hai. Iske 50 g namune mein kitna calcium hoga, agar yeh sach mein ek mineral (fixed banaavat) hai?

20 g. Fixed banaavat ka matlab anupaat same: calcium = 4/10 = 40%. 50 g ka 40% = 20 g. (Yeh calcite, CaCO₃, ka asli anupaat hai.)

F · Aage

📚 Aur Padho (External Reference)

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💖 CharuMam Motivation

Aaj aapne dekha ki heera aur graphite dono sirf carbon hain. Fark sirf itna hai ki heere ke atom bahut lambe samay tak dharti ke andar garmi aur dabaav mein mazbooti se jud gaye.

Aap bhi aise hi ho, beta. Mehnat aur mushkil ka dabaav aapko todne nahi, chamkane aata hai. Aur yaad rakho, quartz ki tarah kathor bano par apni paardarshita (sachchai) mat khona. Aaj ghar ke paas ek patthar uthao aur use dhyaan se dekho: kitne minerals dikhe? Bas, yahi science hai! 🌱

— CharuMam

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