Class 8 Science Ch 8 NCERT Solutions Hinglish mein

Curiosity, Class 8 Science textbook (Reprint 2026-27), ke Chapter 8, Nature of Matter: Elements, Compounds, and Mixtures, ke har sawaal ke jawab: Probe and ponder, paanchon activities aur text ke sawaal, A step further boxes, Keep the curiosity alive ke saare baarah sawaal, aur Discover, design, and debate. Page number book ke hisaab se hain (pages 116–133). Short notes: Chapter 8 ke notes.

Chapter 8 ka mind map: mishran, shuddh padaarth, tatva, yaugik, mishran ya yaugik, aur aas-paas ke istemaal — Poora chapter ek page par

Probe and ponder (page 116)

Tasveer mein kya padaarth (matter) hai? Ped, ghaas aur phool, ball, seedhiyaan aur railing, kitaabein, paani ki bottle, bag, chhadi, kapde aur joote, hawa aur khud bachche padaarth hain, kyunki inka bhaar hai aur ye jagah gherte hain. Dhoop, garmi, khel ki awaaz, parchhaaiyaan, aur bachchon ke vichaar aur bhaavnaayein padaarth nahi hain.

Padaarth ya nahi: jinka bhaar hai aur jo jagah gherte hain, aur jo nahi — Padaarth ya nahi?

Tatvon ko jodkar yaugik banaana. Iske liye chemical reaction chahiye, aksar garmi ya bijli ki madad se: iron aur sulfur saath garam karne par iron sulfide, hydrogen aur oxygen se paani, aur sodium aur chlorine se sodium chloride banta hai, har ek nishchit anupaat mein.

Carbon dioxide sokhne wala yaugik paryavaran ki kaise madad kar sakta hai? Wo hawa ya factory ki chimneyon se carbon dioxide nikaal sakta hai, jisse Prithvi ko garam karne wali greenhouse gas kam ho aur climate change dheema pade. Lime water chhote paimaane par yahi karta hai: calcium hydroxide carbon dioxide sokh kar calcium carbonate banaata hai (Activity 8.1).

Mishran aur hawa (pages 117–120)

Aas-paas ke non-uniform mishran: ret aur kankad, gandla paani, fruit salad, mile-jule meve, paani par tairta tel. Uniform mishran: namak ka paani, nimbu paani, sirka, soda water, hawa, peetal aur stainless steel.

Activity 8.1. Chuna (quicklime) paani ke saath tezi se react karta hai, sisakta hai aur garmi deta hai, aur calcium hydroxide banta hai; chhaana hua ghol, lime water, saaf aur berang hai. Kuch ghante khula chhodne aur beech-beech mein hilaane par ye doodhiya ho jaata hai. Kyon? Hawa ki carbon dioxide calcium hydroxide se react karke na ghulne wale calcium carbonate ke nanhe safed kan banaati hai: calcium hydroxide + carbon dioxide → calcium carbonate + paani. Matlab hawa mein carbon dioxide hai.

Activity 8.1: chune se lime water banta hai, jo hawa mein khula chhodne par doodhiya ho jaata hai — Activity 8.1: hawa mein carbon dioxide

Dhoop ki kiran mein chamakte kan, aur Activity 8.2. Ye dhool hai. Khidki ke paas chhodi kaali sheet par nanhe kan jam jaate hain, jo magnifying glass se aasaani se dikhte hain. Dhool hawa mein latki rehti hai par hawa ka hissa nahi; ye pradooshak hai jiski maatra aur kism samay aur jagah ke saath badalti hai.

Table 8.1, teesra column. Hawa: uniform. Soda water: uniform; paani mein ghuli oxygen: uniform. Hawa mein carbon ke kan: non-uniform. Sirka: uniform; tel aur paani: non-uniform. Ret aur paani: non-uniform; samudra ka paani: uniform. Baking powder: non-uniform; alloys: uniform.

Table 8.1 bhara hua: components ki avastha ke hisaab se mishranon ke prakaar, aur har ek uniform hai ya nahi — Table 8.1: mishranon ke prakaar

A step further (page 121). Doodh, packet wala fruit juice aur mitti mishran hain; baking soda aur cheeni shuddh padaarth (yaugik) hain.

Label par aur science mein shuddh ka matlab, doodh, fruit juice, mitti, baking soda aur cheeni ki chhantaai ke saath — Shuddh ka matlab kya hai?

Activities 8.3 aur 8.4: tatva aur yaugik (pages 121–125)

Activity 8.3. Dono terminals par gas ke bulbule bante hain. Maatra barabar nahi: ek tube mein doosri se lagbhag doguni gas jama hoti hai. Pehli tube par jalti mombatti pop ki awaaz deti hai, to ismein hydrogen hai; doosri par lau aur tez ho jaati hai, to ismein oxygen hai. Kya ye gases bhaap ho sakti hain? Nahi; bhaap thandi hokar waapas paani ban jaati. Physical ya chemical badlaav? Chemical: paani naye padaarthon, hydrogen aur oxygen, mein tootta hai.

Activity 8.3: 9 V battery se paani ko hydrogen aur oxygen mein todna, aur dono gases ki jaanch — Activity 8.3: paani ka vibhaajan

Kya sodium chloride ko physical tareekon se uske tatvon mein toda ja sakta hai? Nahi. Bhaap banaana sirf ghule namak ko paani se alag karta hai; sodium aur chlorine chemical roop se jude hain aur sirf chemical badlaav se alag ho sakte hain.

Activity 8.4. Cheeni pighalti hai, bhoori hoti hai aur phir jalkar kaali ho jaati hai, aur boiling tube ke khule munh ke paas paani ki boondein banti hain. Paani cheeni se aaya, hawa se nahi, kyunki tube garam ho rahi thi. Peechhe carbon (charcoal) bachta hai, jo lau mein garam karne par koyle ki tarah dehakta aur jalta hai. Isliye cheeni carbon, hydrogen aur oxygen ka yaugik hai.

Activity 8.4: garam cheeni bhoori, phir kaali hoti hai, carbon chhodti hai aur paani deti hai — Activity 8.4: cheeni garam karna

Activity 8.5: iron aur sulfur (pages 125–128)

Kya Sample A uniform hai? Nahi, non-uniform hai: dhoosar-kaala iron aur peela sulfur ab bhi alag padaarthon ki tarah dikhte hain. Table 8.2 neeche bhari hui hai.

Activity 8.5: Sample A, iron aur sulfur ka mishran, aur Sample B, iron sulfide, chhah jaanchon mein — Activity 8.5: Sample A aur Sample B

Charcha ke mudde. Dono samples ek jaise nahi dikhte. Sirf Sample A magnetic hai. Sample A ke components magnet se alag ho jaate hain; Sample B ke nahi. Dono se gas banti hai, par alag: Sample A se hydrogen, jismein koi gandh nahi, aur Sample B se hydrogen sulfide, jisse sade ande jaisi badboo aati hai. Chhantaai: iron, sulfur aur hydrogen tatva hain; iron sulfide, iron chloride aur hydrogen sulfide yaugik hain; Sample A aur dilute hydrochloric acid (paani mein ghula hydrogen chloride) mishran hain. Sample B par magnet kyon nahi chalta: usmein iron sulfur se chemical roop se judkar naya yaugik ban chuka hai.

Keep the curiosity alive (pages 131–132)

1. (iv): A aur B tatva hain, jabki C nishchit banaavat wala yaugik hai.

2. (i): Assertion aur Reason dono sahi hain, aur Reason, Assertion ko sahi samjhata hai.

3. Hydrogen ek gas hai jo pop ke saath jalti hai aur indhan ki tarah kaam aati hai; oxygen ek gas hai jo cheezon ko jalne mein madad karti hai. Inse bana paani kamre ke taapmaan par liquid hai, jalta nahi aur aag bujhaane mein kaam aata hai. Matlab yaugik ke gun uske tatvon se bilkul alag hain.

Yaugik kuch naya hai: hydrogen aur oxygen se paani; sodium aur chlorine se namak — Yaugik kuch naya hai

4. Sirf (iii) sahi hai: carbon dioxide, loha, oxygen aur cheeni, har ek mein ek hi tarah ke kan hain. (i) galat hai kyunki paani yaugik aur hawa mishran hai. (ii) galat hai kyunki mineral ki banaavat nishchit hoti hai, isliye wo mishran nahi. (iv) galat hai kyunki hawa aur peetal uniform mishran hain.

Padaarth ki chhantaai: mishran, uniform ya non-uniform, aur shuddh padaarth, tatva ya yaugik — Padaarth ki chhantaai

5. Tatva: iron, magnesium aur oxygen, jo aur saral padaarthon mein nahi tootte. Yaugik: iron oxide aur magnesium oxide, tatva nishchit anupaat mein chemical roop se jude aur naye gunon wale; nam hawa ki bhaap bhi yaugik hai. Mishran: khud nam hawa, gases aur bhaap bina kisi nishchit anupaat ke mile hue.

6. Tatva: aluminium, sona, oxygen, nitrogen, sulfur, hydrogen. Yaugik: carbon dioxide, magnesium oxide, jang (iron oxide), iron sulfide, glucose, paani, sodium chloride, baking soda. Mishran: ret, samudra ka paani, gandla paani, hawa, fruit juice. Shuddh padaarth: saare tatva aur yaugik, kul chaudah.

Question 6: unnees padaarth tatva, yaugik aur mishran mein chhaante hue — Question 6: padaarthon ki chhantaai

7. Iron sulfide. Mishran ke ulat, ye kaala aur har jagah ek jaisa hai, magnet ise nahi kheenchta, iske iron aur sulfur physical tareeke se alag nahi hote, aur dilute hydrochloric acid ke saath ye hydrogen ki jagah hydrogen sulfide deta hai, jisse sade ande jaisi badboo aati hai. Word equation: iron + sulfur → iron sulfide.

Mishran ya yaugik: kaise bante hain, anupaat, gun, alag karna aur misaalein — Mishran ya yaugik?

8. Nahi. Tatva aur saral padaarthon mein nahi tootta, jabki yaugik do ya zyada tatvon ka chemical jod hai aur chemical badlaav se toot sakta hai. Koi padaarth dono nahi ho sakta.

9. Paani liquid nahi, do gases ka mishran hota. Lau ke paas wo jalta ya phat bhi jaata, kyunki hydrogen indhan hai aur oxygen jalne mein madad karti hai, isliye wo aag nahi bujha paata. Hum use pee nahi paate, na usse khaana bana paate, na kuch dho paate, uski banaavat badalti rehti, aur jaisa jeevan hum jaante hain wo sambhav nahi hota.

10. Gas A hydrogen hai. Word equation: iron + dilute hydrochloric acid → iron chloride + hydrogen.

Question 10: dilute hydrochloric acid mein iron ka boora hydrogen gas deta hai — Question 10: gas A kya hai?

11. Paani (hydrogen aur oxygen): peene aur khaana banaane mein; aag bujhaane mein. Carbon dioxide (carbon aur oxygen): paudhe isse khaana banaate hain; fire extinguisher mein aur soda water mein bulbule ke liye.

12. Sona chattanon mein shuddh tatva ki tarah milta hai, isliye wo native mineral hai; aur wo tatva ek metal hai: chamakdaar, peet kar chaadar banne wala aur bijli ka achha chaalak.

Minerals: shuddh tatva wale native minerals aur yaugik wale minerals, aur unse bane products — Minerals

Discover, design, and debate (page 133)

Comic strips: jaise iron aur sulfur do dost hain jo saath khade hokar bhi apne jaise rehte hain (mishran), par ek ‘garam’ mulaakaat ke baad naya kirdaar, iron sulfide, ban jaate hain (yaugik). Khojein: phosphorus Hennig Brand ne 1669 mein khoja, sodium ko Humphry Davy ne 1807 mein bijli se pehli baar alag kiya, penicillin Alexander Fleming ne 1928 mein khoja, kaansa 5,000 saal se zyada se ban raha hai, aur stainless steel 20th century ki shuruaat mein bana. Labels: snacks par masaala mix aur khaane ka tel jaise mishran, aur namak (sodium chloride) aur cheeni jaise yaugik likhe hote hain; detergents par washing soda jaise yaugik. Bahas: har shreni zaroori hai; tatvon se sab kuch banta hai, paani aur dawaaiyon jaise yaugik hamein zinda rakhte hain, aur hawa, alloys aur khaane jaise mishran roz hamare aas-paas hain.

NCERT Solutions Class 8 Science Chapter 8: Nature of Matter: Elements, Compounds, and Mixtures (Hinglish)