Chemistry Today Jan 2021

 

EKLAVYA MODEL RESIDENTIAL SCHOOL (EMRS)

 

Aryabhata satellite launching day

 ​​आर्यभट्ट (उपग्रह) प्रक्षेपण दिवस : 19 अप्रैल

वर्ष 1975 में आज ही के दिन देश के पहले सेटेलाइट 'आर्यभट्ट' को अंतरिक्ष में पृथ्वी की कक्षा में भेजा गया था।

आर्यभट्ट (उपग्रह) : 

•  19 अप्रैल 1975 को इसरो (ISRO) ने भारत के पहले कृत्रिम स्वदेशी उपग्रह (Artificial Satellite) आर्यभट्ट (Aryabhata) का प्रक्षेपण किया था.

•  19 अप्रैल 1975 को लॉन्च किए गए भारत के इस पहले वैज्ञानिक उपग्रह का वजन 360 किलोग्राम था।

•  इस उपग्रह को भारत में ही बैंगलोर के पास पीन्या में Indian Space Research Organisation (इसरो) द्वारा तैयार किया गया था। परन्तु लॉन्च करने में अक्षम होने के कारण सोवियत यूनियन की मदद ली गई।

•  सोवियत यूनियन (रूस) ने अपने इंटर कॉस्मॉस अंतरिक्ष यान की मदद से उपग्रह को पृथ्वी की कक्षा में स्थापित किया। इसके एवज में वर्ष 1972 में इसरो के यू. आर. राव ने सोवियत संघ रूस के साथ एक एग्रीमेंट साइन किया था जिसके तहत रूस भारतीय बंदरगाहों का इस्तेमाल जहाजों को ट्रैक करने के लिए कर सकता था। 

•  कृत्रिम उपग्रहों के निर्माण और अंतरिक्ष में उनके संचालन में अनुभव पाने के मकसद से आर्यभट्ट को डिजाइन किया गया था। इसका मुख्य उद्देश्य एक्स-रे, खगोल विद्या, वायुविज्ञान एवं सौर भौतिकी से जुड़ें प्रयोग करना था। 

•  यह भारत का पहला वैज्ञानिक उपग्रह था जो लॉन्च होने के 17 साल बाद 11 फरवरी 1992 को पृथ्वी पर वापस आया था।

नामकरण :

•  इस उपग्रह का नाम भारत के प्रसिद्ध खगोलशास्त्री और गणितज्ञ आर्यभट्ट के नाम पर रखा गया था। आर्यभट्ट उन पहले व्यक्तियों में से एक थे जिन्होंने बीजगणित का प्रयोग किया था। इसके अलावा उन्होंने पाई का सही मान 3.1416 निकाला था।

•  रिजर्व बैंक ने इस ऐतिहासिक उपलब्धि के पक्ष में वर्ष 1976 से 1997 के बीच 2 रुपए के नोट पर सैटेलाइट की तस्वीर लगाई थी।

JEE Main 2020 Topper Interview

 Parth Dwivedi (100 Percentile):

 Parth Dwivedi is one of those 9 students who secured 100 percentile in JEE Main 2020 Paper 1. Initially shocked upon knowing his JEE main result, Parth has secured 100 marks in Mathematics, 96 marks in Physics, and 96 marks in Chemistry. Consistently working hard to achieve success, Parth started off his IIT dream from 11th standard by commencing his preparation. For him, his father has always been an inspiration. A student of Allen Institute, Parth believes that his teachers helped him a lot to achieve his success. Much satisfied with his scores, this JEE main topper is now preparing to appear for JEE Advanced. Careers360 presents a JEE Main 2020 topper interview, Parth Dwivedi in which he specifies his secrets to his success.

Parth Dwivedi own views, let me write a few of my flaws -

1. I am insecure about myself. More than the happiness of achieving success, I feel the fear of losing it one day.
2. I can lose sight of the bigger picture, and I mean the much bigger picture. Being so engrossed in self betterment, studies and perfection, I tend to overlook why I am doing it. So, instead of making me happy, it can also make me more stressed.
3. I am really bad at accepting compliments, though they make me feel great, but I am not really sure whether to accept it or tell the truth, which connects to the next point…
4. I am not really sure that I deserve what I got. Though I state the contrary emphatically innumerable times, it is more to convince me than anyone else.
5. I am bad at being patient, it is difficult to listen to things that I have already listened to.
6. I enjoy gossip. As I loathe this about myself, I go to great lengths to avoid any, but even then some seeps in and I can’t help but listen to it. But it is just a question of willpower.

Writing all my flaws would take a lifetime, but these are a few of them, at least.

Oh, and also, commas are ubiquitous in my answers. Every time I am in doubt, I use one.

So, why should anyone follow me here?

Because sometimes one needs an answer with minimum biases and prejudices, which seep into one's mind with age.

Sometimes one needs to look at things from the perspective of a child.

Click here to listen in his own words

Acetone and uses

 Acetone, a colorless liquid also known as Propanone, is a solvent used in manufacture of plastics and other industrial products. Acetone may also be used to a limited extent in household products, including cosmetics and personal care products, where its most frequent application would be in the formulation of nail polish removers. Acetone occurs naturally in the human body as a byproduct of metabolism.

Uses and benefits-

Acetone is a primary ingredient in many nail polish removers. It breaks down nail polish, making it easy to remove with a cotton swab or cloth. It is widely used because it can easily mix with water and evaporates quickly in the air.

Acetone is widely used in the textile industry for degreasing wool and degumming silk.

As a solvent, acetone is frequently incorporated in solvent systems or “blends,” used in the formulation of lacquers for automotive and furniture finishes. Acetone also may be used to reduce the viscosity of lacquer solutions.

Source-

www.chemicalsafetyfacts.org

Click here to know more about it

Word Art Day-2021

विश्व कला दिवस : 2021

उद्देश्य :

प्रत्येक वर्ष 15 अप्रैल को कलात्मक अभिव्यक्तियों की विविधता के बारे में जन जागरूकता के उद्देश्य से विश्व कला दिवस समारोह आयोजित किए जाते हैं जो कलाकारों के सतत विकास में योगदान को उजागर करने के साथ ही कलात्मक कृतियों व समाज के बीच संबंधों को सुदृढ़ करने में सहयोग करते हैं।

Click here to know more about World Art Day 2021

Click here to know about it in hindi

Man Ke Mate mat Chaliye मन के मते न चलिए

      मन तो मन है। कभी डगमगाता है तो कभी चट्टान की तरह खड़ा हो जाता है। कभी आसमाँ के तारे तोड़ने की सोचता है तो कभी ताश के पत्तों की तरह ढह जाता है। मन के जंची तो भयंकर पसीने से भीगा शरीर भी मुस्कुराता हुआ दौड़-धपाड़ कर लेगा और नहीं जंची तो पंचमेवे की मिठाई को भी नकार देगा। भक्ष्याभक्ष्य के मानक मन ही स्थापित करता है

   बादलों की उमड़-धुमड़ किसी का मन हर लेती है तो किसी का मन उसे देख भारी हो जाता है। कोई मन-मुटाव के खेल खेलकर मनगढ़ंत दुःख गढ़ लेता है तो कोई मनमौजी अंदाज़ में रूठी रानी के सौंदर्य का महिमामंडन कर उखड़े मन को भी मोह लेता है।

कुछ लोग ताजिन्दगी मन का मैल मन में ही रखते हैं कुछ लोग मन में अद्भुत विचारों को सजा कर रखते हैं। कुछ लोगों का मन कहीं उलझ जाता है तो सुलझने का नाम नहीं लेता, और कुछ लोगों का मन एक बार सुलझ जाता है तो मजाल है दुनियां की कोई ताकत उसको उलझा दे।

मन कच्चा है तो फौलादी मांसपेशियां भी कुछ नहीं कर पायेगी, और मन मजबूत है तो उखड़ती स्वांसों में भी प्राण भर आता है।

जीवन में सबकुछ मनभाया हो, ऐसा सदैव होता नहीं है। सुख और दुःख जीवन के दो शाश्वत अनुभव है लेकिन संसार में इन दोनों का मनगढन्त रूप ज्यादा प्रचलन में है।

एक मन कहता है मैं अपने सारे अवसर खो चुका हूँ दूसरा मन कहता है जो जीवन इतने अवसर खोकर भी टिक गया वह अवसरों के भरोसे थोड़े ही जीता है।

एक मन कहता है मुझे दुनियां ने धोखे ही धोखे दिए हैं तो दूसरा मन कहता चलो, अब बहुतेरे धोखेबाज मेरा कुछ नहीं बिगाड़ सकते। मैं अधिक अनुभवी हूँ।

एक मन कहता है "मैं जिन्दगी में इससे भी ज्यादा पाने का हकदार था" दूसरा मन कहता है "अगर पहली बात सच रही है तो अभी भी तुम उसी प्रकार के हकदार हो"

एक मन अक्सर अपनी खराब आदत के अनुसार हर चीज़ को पाने खोने का एहसास करता हुआ दुःखी और खुश रहने का दिखावा करता है तो दूसरा मन दुःखी दिखता हुआ भी नीले आकाश के नीचे स्थित हर चीज़ को जीने का साधन समझता है ना कि जीवन का उद्देश्य; तो उसके सुखों का अनुभव आप उसके जैसा बनकर ही कर सकते हैं।

सन्त कबीर ने सभी ग्रंथों का सार कितने सरल शब्दों में रख दिया।

मन के मते न चलिए, मन के मते अनेक,

जो मन पर असवार है, सो साधु कोई एक।।

मन को रोजाना नहलाये। मन की अद्भुत सत्ता संसार के संपर्क में आकर मैली ज्यादा होती है। मन के घोड़े पर आप सवार है, और लगाम आपके हाथ में है तो आपका गंतव्य तक पहुंचना तय है।

✒️अर्जुन सिंह साँखला, प्राचार्य, लक्की इंस्टिट्यूट, जोधपुर।

World Haemophilia Day -2021

 विश्व हीमोफीलिया दिवस (World Haemophilia Day) :17 अप्रैल

 

उद्देश्य :
•  इस दुर्लभ रोग के प्रति लोगों में जागरूकता फैलाना।
शुरुआत :
•  17 अप्रैल,1989 को वर्ल्ड फेडरेशन ऑफ हीमोफीलिया (WFH) ने, संस्थापक फ्रैंक श्नाबेल (Frank Schnabel's) के सम्मान में उनके जन्मदिवस को विश्व हीमोफीलिया दिवस के रूप में मनाने की घोषणा की थी और 17 अप्रैल,1990 को यह दिवस पहली बार मनाया गया।
क्या है हीमोफीलिया :
•  यह एक दुर्लभ आनुवांशिक रक्तस्राव विकार है जिसमें रक्त का थक्का ठीक से नहीं बन पाने के कारण व्यक्ति को चोट लगने पर रक्तस्त्राव (ब्लीडिंग) लम्बे समय तक रुकता नहीं है। ऐसा क्लॉटिंग फैक्टर्स नामक एक प्रोटीन की कमी के कारण होता है। इसके अलावा इसमें आंतरिक रक्तस्त्राव का भी खतरा बना रहता है।
पहचान :
•  इस वंशानुगत रोग की पहचान जेनेटिक टेस्टिंग द्वारा की जाती है। हीमोफीलिया से ग्रसित मरीजों के लिए यह टेस्ट काफी विश्वसनीय माना जाता है।
क्या उपचार संभव है ?
•  जीन थेरेपी के जरिए इस रोग का ईलाज किया जाता है जिसकी दवा हाल ही में रोगियों पर असरकारक सिद्ध हुई है।
•  सेंटर फॉर डिजीज कंट्रोल एंड प्रीवेंशन के अनुसार, "हीमोफीलिया का इलाज मिसिंग ब्लड क्लॉटिंग फैक्टर को हटाकर किया जा सकता है।" इसके अलावा इसके उपचार में इंजेक्शन का सहारा भी लिया जाता है। यह एक मेडिकल प्रक्रिया है जो डॉक्टरों की विशेष टीम की देखरेख में पूरी होती है।

Rescheduled of JNVST 2021

It is to inform that Jawahar Navodaya Vidyalaya Selection Test-2021 for admission of students in Jawahar Navodaya Vidyalayas to Class VI for the session 2021-22 which will be conducted on "11.08.2021" in all the states and UTs other than Mizoram, Nagaland and Meghalaya is postponed due to administrative reasons. As per Twitter of Ministry of education. 

The rescheduled date will be notified at least 15 days prior to the date of selection test. 

JNVST 2021 : Ministry of education JNVST 2021 11 August , 2021 को आयोजित hogi. उम्मीदवार इससे संबंधित किसी भी सूचना के लिए Navodaya Vidyalaya की आधिकारिक वेबसाइट navodaya.gov.in पर जाकर देख सकते हैं. मिजोरम, नागालैंड और मेघालय में होने वाली परीक्षा (JNVST 2021) भी स्थगित कर दी गई है. परीक्षा (JNVST 2021) की नई तारीख की सूचना परीक्षा की तारीख से 15 दिन पहले उम्मीदवारों को दी जाएगी.

Metals and non-metals-Important question with answer

 CHAPTER-3 METALS AND NON METALS

MULTIPLE CHOICE QUESTIONS

1.    1.  Which of the following is not a property of metals?

        (a)  Conduction

     (b)  Sonorous    

      (c)  Dullness

      (d)  Ductility

  2.      Metals are refined by using different methods .Which of the following metal is refined by electrolytic refining?

                 (i) Au (ii) Cu (iii) Na (iv) K

        (a)  (i) and (ii)

        (b)  (i) and (iii)G

        (c)  (ii) and (iii)

        (d)  (iii) and (iv)

    3.       Which of the following contains mercury as one of its constituents?

           (a)  Stainless Steel

       (b)  Alnico

        (c) Solder

        (d) Zinc amalgam

    FILL IN THE BLANKS

    4.        Aqua  regia consists of         parts of conc. HCl and       parts of conc HNO3.

    5.                                     is a liquid non-metal.

    6.                          is an amphoteric oxide.

     ONE MARK QUESTIONS

    7.      Name one metal which is a good conductor of electricity and one which is a poor conductor of electricity.

        8.      Why are food cans coated with tin and not with zinc?

        9.      Give the role of anhydrous calcium chloride in the process of roasting.

        ASSERTIONS AND REASONS

        For the question numbers 10, 11 and 12, two statements are given- one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

      (a) Both A and R are true and R is the correct explanation of A.

   ( b) Both A and R are true but R is not the correct explanation of A

       c) A is true but R is false.(

      d) A is false but R is true

     10 . assertion: Iron is found in the free state in nature. 

            Reason: Iron is a highly reactive element.

       11.    Assertion: The thermite welding process is based on reducing the property of iron.

         Reason:    The reduction of metal oxide to form metal by using aluminium powder is called thermite reaction.

      12.    Assertion: Magnesium chloride is covalent.

      Reason:    Metals and non-metals react by mutual transfer of electrons.

     THREE MARK QUESTIONS1

3.  (a) A zinc rod was dipped in the CuSO4 solution. After a certain time, copper from the solution was deposited on the zinc rod. State the reason why did it happen. Give the chemical equation of the reaction involved.(b)Why should the metal sulphides and carbonates be converted to metal oxides in the process of extraction of metal from them?An ore on heating in air produces sulphur dioxide.

         (a) Which process would you suggest for its concentration?

         (b)  Describe briefly any two steps involved in the conversion of concentrated ore into related metal.

      15.    Give a reason for the following:

        (a) Ionic compounds have a high melting point and boiling point.

        (b) Ionic compounds conduct electricity in a molten state.

        (c) Ionic compounds are solids at room temperature and are somewhat hard.

     16.    What happens when

        (i)  ZnCO3 is heated in the absence of oxygen?

        (ii)  A mixture of Cu2O and Cu2S is heated?

        (iii)   A copper coin is kept immersed in a solution of silver nitrate for some time.

        FIVE MARK QUESTIONS

        17.    (a) In the formation of compounds  between two atoms A and B, A loses two electrons and  B gains one electron.

             (i)  What is the nature of the bond formed between A and B?

            (ii)  Suggest the formula of the compound formed between A and B.

            (b) Explain the formation of the MgCl2 molecule.

            (c) Write the electron dot structure of oxygen.

        18.    (a)What is meant by the refining of metals?

        (b)Generally, no hydrogen gas is evolved when metals react with dilute nitric acid. Why? (c)Write the chemical name of the coating that is formed  on silver and copper articles. (d)How do the properties of iron change when:

            (i)  A small quantity of carbon is mixed with it? 

         (ii)Nickel and chromium  are  mixed with it?

       19.    (a)You are provided with three metals Sodium, Magnesium, and copper. Using only water as the reactant how will you identify them?

         (b)Hydrogen is not a metal but it has been assigned a place in the reactivity series of metals. Explain.

        20.    CASE STUDY

            Answer question numbers 20 (a) to 20 (d) based on your understanding of the following paragraph and the related studied concepts.

        A customer approached a newly  trained Goldsmith and asked him to make ornaments. For   this, he gave advance money. The Goldsmith bought a bar of 24-carat gold and tried to make ornaments from it. He was not as successful as the gold was too soft to handle.  He approached a trained goldsmith who  advised him to  use 22-carat gold for this  purpose and this time he was successful and could make the ornaments.

    (a) What is the difference between 24-carat gold and 22-carat gold? 

      (b)Does gold corrode in saltwater?

       (c) Name the chemical which can dissolve gold.

       (d) Why is 22-carat gold used in making ornaments?

कक्षा सीबीएसई की 10वीं और 12वीं कक्षा की बोर्ड परीक्षाएं रद्द करने

 

कोरोना संक्रमण के बढ़ते मामलों को देखते हुए शिक्षा मंत्रालय ने कक्षा सीबीएसई की 10वीं और 12वीं कक्षा की बोर्ड परीक्षाएं रद्द करने का फ़ैसला किया है.

शिक्षा मंत्री रमेश पोखरियाल निशंक ने सोशल मीडिया पर  जानकारी दी है कि 10वीं के नतीजे इंटरनल एसेसमेंट यानी बोर्ड के बनाए ऑबजेक्टिव क्राइटेरिया के आधार पर किए जाएंगे.

वहीं 12वीं की परीक्षा को फ़िलहाल टाल दिया गया है. 12वीं की परीक्षा कराने को लकर बाद में फ़ैसला किया जाएगा.

मंत्रालय का कहना है कि इसके लिए एक जून को एक बार फिर स्थिति की समीक्षा की जाएगी.

परीक्षा प्रवेश पत्र : JNVST Admit Card Download

 परीक्षा प्रवेश पत्र : JNVST Admit Card Download 

जवाहर नवोदय विद्यालय  चयन परीक्षा 2022 वर्ग छह के लिए , जो 30 April 2022 को होना सुनिश्चित है ,का प्रवेश पत्र जारी कर दिया गया है । वैसे अभ्यर्थी जिसने वर्ग छह हेतु  पंजीकरण करवाया है , नवोदय विद्यालय समिति के वेवसाइट पर जाकर प्रवेश पत्र download कर सकते है । अथवा नीचे उपलब्ध link का प्रयोग कर भी Admit Card download कर सकते है ।

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Click here to download admit card for JNVST Class VI entry exam 2021

Class IX Lateral entry selection test result 2023

 

जवाहर नवोदय विद्यालय  चयन परीक्षा 2023 वर्ग IX के लिए lateral entry exam , जो  2023 को हुई थी उसका रिजल्ट रोल नंबर wise नीचे दिए गए लिंक पर आप देख सकते हैं I

Click here to see class IX lateral entry exam result 2023

CBSE Chemistry syllabus 2021-22

 CLASS - XII) (2021-22)            

                                 (THEORY)

Total Periods (Theory 160 + Practical 60)

Time : 3 Hours                              70 Marks

Unit No.	Title	No. of Periods	Marks
Unit I	Solid State	10	23
Unit II	Solutions	10
Unit III	Electrochemistry	12
Unit IV	Chemical Kinetics	10
Unit V	Surface Chemistry	08
Unit VI	General Principles and Processes of Isolation of Elements	08	19
Unit VII	p -Block Elements	12
Unit VIII	d -and f -Block Elements	12
Unit IX	Coordination Compounds	12
Unit X	Haloalkanes and Haloarenes	10	28
Unit XI	Alcohols, Phenols and Ethers	10
Unit XII	Aldehydes, Ketones and Carboxylic Acids	10
Unit XIII	Amines	10
Unit XIV	Biomolecules	12
Unit XV	Polymers	08
Unit XVI	Chemistry in Everyday Life	06
	total	160	70

Unit I:   Solid State                                       10 Periods

   Classification of solids based on different binding forces: molecular, ionic, covalent and metallic solids, amorphous and crystalline solids (elementary idea). Unit cell in two dimensional and three dimensional lattices, calculation of density of unit cell, packing in solids, packing efficiency, voids, number of atoms per unit cell in a cubic unit cell, point defects, electrical and magnetic properties.

Band theory of metals, conductors, semiconductors and insulators and n and p type  semiconductors.

Unit II: Solutions                                          10 Period

   Types of solutions, expression of concentration of solutions of solids in liquids, solubility of gases in liquids, solid solutions, Raoult's law, colligative properties - relative lowering of vapour pressure, elevation of boiling point, depression of freezing point, osmotic pressure, determination of molecular masses using colligative properties, abnormal molecular mass, Van't Hoff factor.

 Unit III: Electrochemistry                              12 Periods

  Redox reactions, EMF of a cell, standard electrode potential, Nernst equation and its application to chemical cells, Relation between Gibbs energy change and EMF of a cell, conductance in electrolytic solutions, specific and molar conductivity, variations of conductivity with concentration, Kohlrausch's Law, electrolysis and law of electrolysis (elementary idea), dry cell-electrolytic cells and Galvanic cells, lead accumulator, fuel cells, corrosion.

Unit IV: Chemical Kinetics                                       10 Periods

  Rate of a reaction (Average and instantaneous), factors affecting rate of reaction: concentration, temperature, catalyst; order and molecularity of a reaction, rate law and specific rate constant, integrated rate equations and half-life (only for zero and first order reactions), concept of collision theory (elementary idea, no mathematical treatment), activation energy, Arrhenius equation.

Unit V: Surface Chemistry                                                         08 Periods

    Adsorption - physisorption and chemisorption, factors affecting adsorption of gases on solids, catalysis: homogenous and heterogenous, activity and selectivity of solid catalysts; enzyme catalysis, colloidal state: distinction between true solutions, colloids and suspension; lyophilic, lyophobic, multi-molecular and macromolecular colloids; properties of colloids; Tyndall effect, Brownian movement, electrophoresis, coagulation, emulsion - types of emulsions.

Unit VI:  General Principles and Processes of Isolation of Elements            08 Periods

     Principles and methods of extraction - concentration, oxidation, reduction - electrolytic method and refining; occurrence and principles of extraction of aluminium, copper, zinc and iron.

Unit VII:p-Block Elements                                                         12 Periods

      Group -15 Elements: General introduction, electronic configuration, occurrence, oxidation states, trends in physical and chemical properties; Nitrogen preparation properties and uses; compounds of Nitrogen: preparation and properties of Ammonia and Nitric Acid, Oxides of Nitrogen (Structure only); Phosphorus - allotropic forms, compounds of Phosphorus: Preparation and properties of Phosphine, Halides and Oxoacids (elementary idea only).

 

    Group 16 Elements: General introduction, electronic configuration, oxidation states, occurrence, trends in physical and chemical properties, dioxygen: preparation, properties and uses, classification of Oxides, Ozone, Sulphur -allotropic forms; compounds of Sulphur: preparation properties and uses of Sulphur-dioxide, Sulphuric Acid: industrial process of manufacture, properties and uses; Oxoacids of Sulphur (Structures only).

  Group 17 Elements: General introduction, electronic configuration, oxidation states, occurrence, trends in physical and chemical properties; compounds of halogens, Preparation, properties and uses of Chlorine and Hydrochloric acid, interhalogen compounds, Oxoacids of halogens (structures only).

 Group 18 Elements: General introduction, electronic configuration, occurrence, trends in physical and chemical properties, uses.

Unit VIII: d and f Block Elements                                             12 Periods

     General introduction, electronic configuration, occurrence and characteristics of transition metals, general trends in properties of the first row transition metals – metallic character, ionization enthalpy, oxidation states, ionic radii, colour, catalytic property, magnetic properties, interstitial compounds, alloy formation, preparation and properties of K2Cr2O7 and KMnO4.

 Lanthanoids - Electronic configuration, oxidation states, chemical reactivity and lanthanoid contraction and its consequences.

  Actinoids - Electronic configuration, oxidation states and comparison with lanthanoids.

Unit IX: Coordination Compounds                            12 Periods

   Coordination compounds - Introduction, ligands, coordination number, colour, magnetic properties and shapes, IUPAC nomenclature of mononuclear coordination compounds. Bonding, Werner's theory, VBT, and CFT; structure and stereoisomerism, importance of coordination compounds (in qualitative analysis, extraction of metals and biological system).

Unit X:   Haloalkanes and Haloarenes.                       10 Periods

  Haloalkanes: Nomenclature, nature of C–X bond, physical and chemical properties, optical rotation mechanism of substitution reactions.

 Haloarenes: Nature of C–X bond, substitution reactions (Directive influence of halogen in monosubstituted compounds only).

 Uses and environmental effects of - dichloromethane, trichloromethane, tetrachloromethane, iodoform, freons, DDT.

Unit XI:  Alcohols, Phenols and Ethers                       10 Periods

 

Alcohols: Nomenclature, methods of preparation, physical and chemical properties (of primary alcohols only), identification of primary, secondary and tertiary alcohols, mechanism of dehydration, uses with special reference to methanol and ethanol.

 Phenols: Nomenclature, methods of preparation, physical and chemical properties, acidic nature of phenol, electrophillic substitution reactions, uses of phenols.

 Ethers: Nomenclature, methods of preparation, physical and chemical properties, uses.

Unit XII: Aldehydes, Ketones and Carboxylic Acids                  10 Periods

 Aldehydes and Ketones: Nomenclature, nature of carbonyl group, methods of preparation, physical and chemical properties, mechanism of nucleophilic addition, reactivity of alpha hydrogen in aldehydes, uses.

 Carboxylic Acids: Nomenclature, acidic nature, methods of preparation, physical and chemical properties; uses.

Unit XIII: Amines                            10 Periods

 Amines: Nomenclature, classification, structure, methods of preparation, physical and chemical properties, uses, identification of primary, secondary and tertiary amines.

Diazonium salts: Preparation, chemical reactions and importance in synthetic organic chemistry.

Unit XIV: Biomolecules            12 Periods

 Carbohydrates - Classification (aldoses and ketoses), monosaccahrides (glucose and fructose), D-L configuration oligosaccharides (sucrose, lactose, maltose), polysaccharides (starch, cellulose, glycogen); Importance of carbohydrates.

Proteins -Elementary idea of - amino acids, peptide bond, polypeptides, proteins, structure of proteins - primary, secondary, tertiary structure and quaternary structures (qualitative idea only), denaturation of proteins; enzymes. Hormones - Elementary idea excluding structure.

Vitamins - Classification and functions.

Nucleic Acids: DNA and RNA.

Unit XV: Polymers                     08 Period

   Classification - natural and synthetic, methods of polymerization (addition and condensation), copolymerization, some important polymers: natural and synthetic like polythene, nylon polyesters, bakelite, rubber. Biodegradable and non-biodegradable polymers.

Unit XVI: Chemistry in Everyday life       06 Periods

  Chemicals in medicines - analgesics, tranquilizers antiseptics, disinfectants, antimicrobials, antifertility drugs, antibiotics, antacids, antihistamines.

Chemicals in food - preservatives, artificial sweetening agents, elementary idea of antioxidants.

Cleansing agents- soaps and detergents, cleansing action.

PRACTICALS

Evaluation Scheme for Examination	Marks
Volumetric Analysis	08
Salt Analysis	08
Content Based Experiment	06
Project Work	04
Class record and viva	04
Total	30

PRACTICAL SYLLABUS                                                  60Periods

Micro-chemical methods are available for several of the practical experiments. Wherever possible, such techniques should be used.

A.      Surface Chemistry

(a)     Preparation of one lyophilic and one lyophobic sol Lyophilic sol - starch, egg albumin and gum

Lyophobic sol - aluminium hydroxide, ferric hydroxide, arsenous sulphide.

(b)    Dialysis of sol-prepared in (a) above.

(c)     Study of the role of emulsifying agents in stabilizing the emulsion of different oils.

 B.      Chemical Kinetics

(a)     Effect of concentration and temperature on the rate of reaction between Sodium Thiosulphate and Hydrochloric acid.

(b)    Study of reaction rates of any one of the following:

(i)      Reaction of Iodide ion with Hydrogen Peroxide at room temperature using different concentration of Iodide ions.

(ii)    Reaction between Potassium Iodate, (KIO3) and Sodium Sulphite: (Na2SO3) using starch solution as indicator (clock reaction).

C.      Thermochemistry

Any one of the following experiments

i)        Enthalpy of dissolution of Copper Sulphate or Potassium Nitrate.

ii)       Enthalpy of neutralization of strong acid (HCI) and strong base (NaOH).

iii)     Determination of enthaply change during interaction (Hydrogen bond formation) between Acetone and Chloroform.

 D.      Electrochemistry

            Variation of cell potential in Zn/Zn²⁺|| Cu²⁺/Cu with change in concentration of electrolytes (CuSO4 or ZnSO4) at room temperature.

 E.       Chromatography

        i)        Separation of pigments from extracts of leaves and flowers by paper chromatography and determination of Rf values.

       ii)       Separation of constituents present in an inorganic mixture containing two cations only (constituents having large difference in Rf values to be provided).

 F.      Preparation of Inorganic Compounds   Preparation of double salt of Ferrous Ammonium Sulphate or Potash Alum. Preparation of Potassium Ferric Oxalate.

 G.      Preparation of Organic Compounds

Preparation of any one of the following compounds

i)        Acetanilide

ii)       Di -benzalAcetone

iii)     p-Nitroacetanilide

iv)     Aniline yellow or 2 - Naphthol Anilinedye.

 H.      Tests for the functional groups present in organic compounds:

Unsaturation, alcoholic, phenolic, aldehydic, ketonic, carboxylic and amino (Primary) groups.

I.        Characteristic tests of carbohydrates, fats and proteins in pure samples and their detection in given foodstuffs.

J.       Determination of concentration/ molarity of KMnO4 solution by titrating it against a standard solution of:

i)        Oxalic acid,

ii)       Ferrous Ammonium Sulphate

(Students will be required to prepare standard solutions by weighing themselves).

K.      Qualitative analysis

Determination of one cation and one anion in a given salt.

Cation : Pb^2+, Cu²⁺ As³⁺, Aℓ³⁺, Fe³⁺, Mn²⁺, Zn²⁺, Cu²⁺, Ni²⁺, Ca²⁺, Sr²⁺, Ba²⁺, Mg²⁺, NH4+

Note: Insoluble salts excluded) PROJECT

Scientific investigations involving laboratory testing and collecting information from other sources

A few suggested Projects.

·           Study of the presence of oxalate ions in guava fruit at different stages of ripening.

·           Study of quantity of casein present in different samples of milk.

·           Preparation of soybean milk and its comparison with the natural milk with respect to curd formation, effect of temperature, etc.

·           Study of the effect of Potassium Bisulphate as food preservative under various conditions (temperature, concentration, time, etc.)

·           Study of digestion of starch by salivary amylase and effect of pH and temperature on it.

·           Comparative study of the rate of fermentation of following materials: wheat flour, gram flour, potato juice, carrot juice, etc.

·           Extraction of essential oils present in Saunf (aniseed), Ajwain (carum), Illaichi (cardamom).

·           Study of common food adulterants in fat, oil, butter, sugar, turmeric power, chilli powder and pepper. Note: Any other investigatory project, which involves about 10 periods of work, can be chosen with the approval of the teacher.

 

Practical Examination for Visually Impaired Students of Classes XI and XII Evaluation Scheme

Time Allowed: Two hours                                                                                                   Max. Marks:30

 

Identification/Familiarity with the apparatus	5 marks
Written test (based on given/prescribed practicals)	10 marks
Practical Record	5 marks
Viva	10 marks
Total	30 marks

 

General Guidelines

·       The practical examination will be of two hour duration.

·       A separate list of ten experiments is included here.

·       The written examination in practicals for these students will be conducted at the time of practical examination of all other students.

·       The written test will be of 30 minutes duration.

·       The question paper given to the students should be legibly typed. It should contain a total of 15 practical skill based very short answer type questions. A student would be required to answer any 10 questions.

·       A writer may be allowed to such students as per CBSE examination rules.

·       All questions included in the question papers should be related to the listed practicals. Every question should require about two minutes to be answered.

     ·       These students are also required to maintain a practical file. A student is expected to record at least five of the listed experiments as per the specific instructions for each subject. These practicals should be duly checked and signed by the internal examiner.

    ·       The format of writing any experiment in the practical file should include aim, apparatus required, simple theory, procedure, related practical skills, precautions etc.

·       Questions may be generated jointly by the external/internal examiners and used for assessment.

     ·       The viva questions may include questions based on basic theory/principle/concept, apparatus/materials/ chemicals required, procedure, precautions, sources of error etc.

 A.      Items for Identification/Familiarity of the apparatus for assessment in practical (All experiments)

  Beaker, glass rod, tripod stand, wire gauze, Bunsen burner, Whatman filter paper, gas jar, capillary tube, pestle and mortar, test tubes, tongs, test tube holder, test tube stand, burette, pipette, conical flask, standard flask, clamp stand, funnel, filter paper

Hands-on Assessment

·       Identification/familiarity with the apparatus

·       Odour detection in qualitative analysis

B.      List of Practicals

The experiments have been divided into two sections: Section A and Section B. The experiments mentioned in Section B are mandatory.

         SECTION- A

 A          Surface Chemistry

(1)    Preparation of one lyophilic and one lyophobic sol Lyophilic sol - starch, egg albumin and gum

(2)    Preparation of one lyophobic sol Lyophobic sol – Ferric hydroxide

B         Chromatography

(1)    Separation of pigments from extracts of leaves and flowers by paper chromatography and determination of Rf values (distance values may be provided).

C         Tests for the functional groups present in organic compounds:

(1)    Alcoholic and Carboxylic groups.

(2)    Aldehydic and Ketonic

D        Characteristic tests of carbohydrates and proteins in the given foodstuffs.

E         Preparation of Inorganic Compounds- Potash Alum

            SECTION-B (Mandatory)

 F         Quantitative analysis

(1)    (a)      Preparation of the standard solution of Oxalic acid of a given volume

(b)      Determination of molarity of KMnO4 solution by titrating it against a standard solution of Oxalic acid.

(2)    The above exercise [F 1 (a) and (b)] to be conducted using Ferrous ammonium sulphate (Mohr's salt)

 G          Qualitative analysis:

(1)    Determination of one cation and one anion in a given salt. Cation –NH ⁺

                 Anions – CO ^2-, S^2-, SO ^2-, Cl^-, CH COO^-

               (Note: Insoluble salts excluded)

 Note: The above practicals may be carried out in an experiential manner rather than recording observations.

Prescribed Books:

1.       Chemistry Part -I, Class-XII, Published by NCERT.

2.       Chemistry Part -II, Class-XII, Published by NCERT.

 CHEMISTRY (Code No. 043) QUESTION PAPER DESIGN CLASSES –XI and XII (2020-21)

S	Domains	Total Marks	%
1	Remembering and Understanding: Exhibit memory of previously learned material by recalling facts, terms, basic concepts and answers. Demonstrate understanding of facts and ideas by organizing, comparing, translating, interpreting, giving descriptions and stating main ideas.	28	40
2	Applying: Solve problems to new situations by applying acquired knowledge, facts, techniques and rules in a different way.	21	30
3	Analysing, Evaluating and Creating: Examine and break information into parts by identifying motives or causes. Make inferences and find evidence to support generalizations. Present and defend opinions by making judgments about information, validity of ideas or quality of work based on a set of criteria. Compile information together in a different way by combining elements in a new pattern or proposing alternative solutions.	21	30

 

1.    No chapter wise weightage. Care to be taken to cover all the chapters.

2.    Suitable internal variations may be made for generating various templates.

Choice(s):

 ·                There will be no overall choice in the question paper.

 ·                However, 33% internal choices will be given in all the sections.