NCERT Exemplar Class 10 Science Chapter 1: Chemical Reactions And Equations
NCERT Class 10 Science Chapter 1 - रासायनिक अभिक्रियाएँ और समीकरण विज्ञान का एक महत्वपूर्ण विषय है, जो हमें रासायनिक परिवर्तन और उनके समीकरणों की समझ प्रदान करता है। इस अध्याय में आप **संयोजन अभिक्रिया, अपघटन अभिक्रिया, विस्थापन अभिक्रिया और द्विविस्थापन अभिक्रिया** के बारे में विस्तार से जानेंगे। यह टॉपिक न केवल आपकी परीक्षा के लिए बल्कि प्रतियोगी परीक्षाओं के लिए भी बहुत उपयोगी है। यहां आपको **NCERT Solutions, महत्वपूर्ण प्रश्न, उदाहरण और विस्तृत व्याख्या** मिलेगी जिससे आप इस विषय में महारत हासिल कर सकें।
NCERT Class 10 Science Chemical Reactions And Equations - Solutions & Notes
इस पेज पर **कक्षा 10 विज्ञान अध्याय 1 - रासायनिक अभिक्रियाएँ और समीकरण** के सभी महत्वपूर्ण प्रश्नों और उनके उत्तरों को विस्तार से समझाया गया है। यह छात्रों के लिए **अवश्य पढ़ने योग्य नोट्स और अभ्यास प्रश्न** प्रदान करता है, जिससे वे परीक्षा में बेहतरीन स्कोर कर सकें।
मुख्य विषय:
- रासायनिक अभिक्रियाएँ (Chemical Reactions): अभिक्रियाओं के प्रकार और उनके उदाहरण।
- रासायनिक समीकरण (Chemical Equations): समीकरणों को संतुलित करने की विधि।
- संयोजन और अपघटन अभिक्रिया: अभिक्रियाओं की प्रक्रिया और उनके उपयोग।
- ऑक्सीकरण और अपचयन (Oxidation & Reduction): रेडॉक्स अभिक्रियाओं की संपूर्ण जानकारी।
- NCERT Solutions: परीक्षा में पूछे जाने वाले महत्वपूर्ण प्रश्न और उनके हल।
NCERT Class 10 Science Chemical Reactions And Equations - PDF Download
यदि आप **NCERT Class 10 Science Chapter 1 Chemical Reactions And Equations PDF Download** करना चाहते हैं, तो इस पेज पर उपलब्ध लिंक का उपयोग करके आसानी से प्राप्त कर सकते हैं। यह अध्ययन सामग्री आपकी परीक्षा की तैयारी को मजबूत बनाएगी।
1. A solution of potassium chloride when mixed with silver nitrate solution, an insoluble white substance is formed. Write the chemical reaction involved and also mention the type of the chemical reaction.
Answer
- KCL(aq) + AgNO3(aq)--------> AgCl(s) + KNO3(aq)
- It is a double displacement reaction. It is also a precipitation reaction as AgCl is a white precipitate.
2. Write the balanced chemical equations for the following reactions.
- (a) Sodium carbonate on reaction with hydrochloric acid in equal molar concentrations gives sodium chloride and sodium hydrogen-carbonate.
- (b) Sodium hydrogencarbonate on reaction with hydrochloric acid gives sodium chloride, water and liberates carbon dioxide.
- (c) Copper sulphate on treatment with potassium iodide precipitates cuprous iodide (Cu2I2), liberates iodine gas and also forms potassium sulphate.
Answer
3. Why do fireflies glow at night?.
Answer
- It is because protein present in fireflies undergoes oxidation in presence of air and an enzyme. This chemical reaction involves emission of visible light. Therefore, fireflies glow at night.
4. Grapes hanging on the plant do not ferment but after being plucked from the plant can be fermented. Under what conditions do these grapes ferment? Is it a chemical or a physical change?.
Answer
- Grapes when attached to plants are living and therefore they have their immune system due to which they cannot get fermented. When microbes attack plucked grapes in absence of air, they undergo fermentation to form alcohol. This is a chemical process.
5. A substance X, which is an oxide of a group 2 element, is used intensively in the cement industry. This element is present in bones also. On treatment with water, it forms a solution which turns red litmus blue. Identify X and also write the chemical reactions involved.
Answer
- The substance ‘X’ is calcium oxide (CaO), element is calcium. Calcium oxide is used in cement industry. Calcium is present in bones in form of calcium phosphate. Calcium oxide dissolves in water forming alkali which turns red litmus blue. CaO(s)
6. Why do we store silver chloride in dark coloured bottles?
Answer
- It is because silver chloride decomposes to silver and chlorine gas in presence of sunlight.
- 2AgCl(s) ----------------> 2Ag(s) + Cl2(g)
7. A magnesium ribbon is burnt in oxygen to give a white compound X accompanied by emission of light. If the burning ribbon is now placed in an atmosphere of nitrogen, it continues to burn and forms a compound
Answer
- Write the chemical formulae of X and Y.
- Write a balanced chemical equation, when X is dissolved in water.
- 2Mg(s) + O2(g) ------------> 2MgO(s) + light
- MgO(s) + H2O(l) ----------> Mg(OH)2(aq)
8.Which among the following changes are exothermic or endothermic in nature?
Answer
- Decomposition of ferrous sulphate
- Dilution of sulphuric acid
- Dissolution of sodium hydroxide in water
- It is exothermic process.
- It is exothermic process.
- It is endothermic process.
9.
On adding a drop of barium chloride solution to an aqueous solution of sodium sulphite, white precipitate is obtained.
Answer
- Write a balanced chemical equation of the reaction involved
- What other name can be given to this precipitation reaction?
- On adding dilute hydrochloric acid to the reaction mixture, white precipitate disappears. Why?
- BaCl2(aq) + Na2SO3(aq) --------> BasO3(s) + 2naCl
10.You are provided with two containers made up of (A) copper and (B) aluminium. You are also provided with solutions of (a) dilute HCl (b) dilute HNO3(c) ZnCl2 and (d) H20. In which of the above containers these solutions can be kept?
Answer
- When solutions are kept in copper container-
- Dilute HC1: No reaction takes place as copper is less reactive than hydrogen. Therefore, dil. HC1 can be kept in copper container.
- Dilute HNOs: Copper will react with dil. HNOs as it is an oxidising agent and will form copper nitrate and nitrogen monoxide gas.
