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MBD Super Refresher English Communicative  MBD Super Refresher English Language & Literature  MBD Super Refresher Hindi Course ‘A’  MBD Super Refresher Hindi Course ‘B’  MBD Super Refresher Mathematics Ph. 22149691, 22147073     MBD Super Refresher Social Science MBD Super Refresher Science MBD Sanskrit MBD Punjabi Contributors Project Manager: Manish Sharma Composition & Layout: Dhirender Singh Negi and Team We are committed to serve students with best of our knowledge and resources. We have taken utmost care and attention while editing and printing this book but we would beg to state that Authors and Publishers should not be held responsible for unintentional mistakes that might have crept in. However, errors brought to our notice, shall be gratefully acknowledged and attended to. © All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means, electronic, mechanical, photocopying, recording, or otherwise without the prior written permission of the publisher. Any breach will entail legal action and prosecution without further notice. Published by: Printed at: MALHOTRA BOOK DEPOT MBD House, Railway Road, Jalandhar City. M. GULAB SINGH & SONS (P) LTD. B-5/14, Site IV, Industrial Area, Shahibabad (U.P.) SYLLABUS SCIENCE (CLASS–X) Second Term Unit No. Unit Marks: 90 Marks I Chemical Substances -Nature and Behaviour 23 II World of Living 30 III Natural Phenomena 29 V Natural Resources 08 Total Theme: Materials 90 (25 Periods) Unit I: Chemical Substances–Nature and Behaviour Carbon compounds: Covalent bonding in carbon compounds. Versatile nature of carbon. Homologous series. Nomenclature of carbon compounds containing functional groups (halogens, alcohol, ketones, aldehydes, alkanes and alkynes), difference between saturated hydrocarbons and unsaturated hydrocarbons. Chemical properties of carbon compounds (combustion, oxidation, addition and substitution reaction). Ethanol and Ethanoic acid (only properties and uses), soaps and detergents. Periodic classification of elements: Need for classification, Modern periodic table, gradation in properties, valency, atomic number, metallic and non-metallic properties. Theme: The World of the Living (30 Periods) Unit II: World of Living Reproduction: Reproduction in animals and plants (asexual and sexual) reproductive health-need and methods of family planning. Safe sex vs HIV/AIDS. Child bearing and women's health. Heredity and Evolution: Heredity; Mendel's contribution- Laws for inheritance of traits: Sex determination: brief introduction; Basic concepts of evolution. Theme: Natural Phenomena (23 Periods) Unit III: Natural Phenomena Reflection of light by curved surfaces; Images formed by spherical mirrors, centre of curvature, principal axis, principal focus, focal length, mirror formula (Derivation not required), magnification. Refraction; Laws of refraction, refractive index. Refraction of light by spherical lens; Image formed by spherical lenses; Lens formula (Derivation not required); Magnification. Power of a lens; Functioning of a lens in human eye, defects of vision and their corrections, applications of spherical mirrors and lenses. Refraction of light through a prism, dispersion of light, scattering of light, applications in daily life. Theme: Natural Resources (12 Periods) Unit : Natural Resources Conservation of natural resources. Management of natural resources. Conservation and judicious use of natural resources. Forest and wild life; Coal and Petroleum conservation. Examples of people's participation for conservation of natural resources. Regional environment: Big dams: advantages and limitations; alternatives, if any. Water harvesting. Sustainability of natural resources. Our environment: Eco-system, Environmental problems, Ozone depletion, waste production and their solutions. Biodegradable and non-biodegradable substances. PRACTICALS—SECOND TERM Practicals should be conducted alongside the concepts taught in theory classes. LIST OF EXPERIMENTS 1.To study the following properties of acetic acid (ethanoic acid): (i)odour (ii) solubility in water (iii) effect on litmus (iv) reaction with sodium bicarbonate 2.To study saponification reaction for preparation of soap. 3.To study the comparative cleaning capacity of a sample of soap in soft and hard water. 4.To determine the focal length of: (i) Concave mirror (ii) Convex lens by obtaining the image of a distant object. 5.To trace the path of a ray of light passing through a rectangular glass slab for different angles of incidence. Measure the angle of incidence, angle of refraction, angle of emergence and interpret the result. 6.To study (a) binary fission in Amoeba, and (b) budding in yeast with the help of prepared slides. 7.To trace the path of the rays of light through a glass prism. 8. To find the image distance for varying object distances in case of a convex lens and draw corresponding ray diagrams to show the nature of image formed. 9.To study homology and analogy with the help of models/charts of animals and models/charts/specimens of plants. 10. To identify the different parts of an embryo of a dicot seed (Pea, gram or red kidney bean). QUESTION PAPER DESIGN (CODE NO. 086/090) Class–X Time: 3 Hours Max. Marks: 90 Very Short S. No. Typology of Questions Answer (VSA) 1 Mark Short Short Long Answer Answer Answer Total –I (SAI) –II (SAII) (LA) Marks 2 Marks 3 Marks 5 Marks % Weight age 1 Remembering (Knowledge based simple recall questions, to know specific facts, terms, concepts, principles, or theories, Identify, define or recite, information) 3 – 1 1 11 15% 2 Understanding (Comprehension - to be familiar with meaning and to understand conceptually, interpret, compare, contrast, explain, paraphrase, or interpret information) – 1 4 1 19 25% 3 Application (Use abstract information in concrete situation, to apply knowledge to new situations, use given content to interpret a situation, provide an example, or solve a problem) – – 4 1 17 23% 4 Higher Order Thinking Skills (Analysis & Synthesis - Classify, compare, contrast, or differentiate between different pieces of information, Organize and/or integrate unique pieces of information from a variety of sources) – 2 – 1 9 12% 5 Inferential and Evaluative (Appraise, judge, and/or justify the value or worth of a decision or outcome, or to predict outcomes based on values) – – 2+1* 2 19 25% Total (Theory Based Questions) 3x1=3 3x2=6 12x3= 36 Practical Based Questions (PBQs) 9x1=9 3x2=6 – Total 12x1=12 6x2=12 12x3= 36 *One question of 3 marks will be included to assess the values inherent in the texts. 6x5=30 75(24) – 15(12) 6x5=30 90(36) 100% Super Refresher All chapters as per NCERT Textbook ments n of Ele Chapter 5) io t a c sifi book T Text ic Clas (NCER Period 2 Every chapter divided into CONCEPTS and each CONCEPT dealt with as a complete topic ts lemen TS tionofE ONCEP EPTS C lassifiofcaa Cell ofCtio CONC Attemptsan isa n ble rlyctural Org riodic Ta Earu 2.1 ’s Pes leev ble 3.1 St ende rganelnlePeriodic Ta 2.22 M ell O 3. 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(1) t wer o a le t The ompa Be e th o a only t berein It w se a r (2) e hre few a K er’s re: eand e M At s appli limita cla elem tria g find ma t c s io d a s ent s fr ble ifica ou ny Ne ns o Ca s. om t. w o p (3) t the ion? Aft land’s laces, nly up f New er t elem la he table. two e to calc nds’ ent disc lem law iu s m k ent ove of o now sw . ry o ctav na ere f no t th es? put at t ble ime gas in t , law . he sam of o e ctav slot ew in o as n r der ot fo to und adju to b st e ev lem alid ent . s in the Each sub-topic dealt with as a complete unit 2/1 8/2 016 7:3 6:5 4P M Science fresher per Re MBD Su 50 -X Science HOTS questions with answers in every chapter ble. riodic ta in the pe E and F B, C, D, ents A, em R 18 el E 17 n of six CORN 16 estions: e positio HOTS 15 C shows th the following qu 14 g table in er w sw llo 13 fo table an 1. 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Y tio na n ou are (ix) Quest n num bers 4 to 3 in d all q each q l choic io to a u e u b t ttem (x) Questio n num ers 7 o 6 ar Section estions estion has b Ma e be to ee x. M Que is n pt b o A stio numb rs 19 18 a two m are o f Sect to be n pro oth ark v r io nn sec s: um ers 25 to 24 e thre arks q ne ma n B a attem ided in tion 90 ber em ues pte re t rk q s to 3 are a . ll s t d a io ob ues the . 25 1. W rks 6 in five ns, e t t t io m q o t h a ob Sec ns. ree h arks uest ttem 33 e t 2. G at is io io q a ans pte que ues ns, nB re o far ive d w t t s io o f t e a p s ion ns o re re one epa oin b rea 3. G to rate f fiv son ma pract s, to b e answ d in a iv f th e ly. rk a b ic e as 4. D e two ee nd al bas answ ered in out 30 y exa to wh e 34 ed ered abo wor SE y th e ? mp q 5. W fine p t o u C d u in e t s 36 les ec TIO erio stio 50 eac abo ed o a o n d r lo f h w s u N eo icity 6. . on b t 70 ord ur o —A f tw . (i) and iodegr wor s eac om Wh ot clea ada f the s ds e h. give arks at is n (ii) ble k ach its eac was y is blu term ponds . cau 7. D Defin h t . o e e s e e. r la s. fo e ? imp kes 8. A fine m lant r relea but et se o at tom an f ov ic n allic ch ion. aqu 10, um um ariu 20, ber aracte fr mn om ro so 7a (a) e f an f fe ova nd Ide we ry ? eds to 14 ntif (b) lem eleme be y th . nt. ent Ide clea ee Ho s ar ntif (c) ned le wd y th eg me .W 9. W Iden iven nts. oes eg hy tify rou it b ? hat e var the pn low of e is b y u p a mb : erio lon iolo cos 10. e g r d y g s so ap st ic Wh of t f th e at is em ? al ma r h iod ese es gnifi ase and elem catio e elem xua dow ent e l re n? na s in pro Wil nts in gro duc per the l th up io tion e le per dic ? vels iod ?D t able ic t iscu o . f a this ble. ss s por m agn e fo ifi rma catio tion nb M-1 ed in fu iffer ngi. ent at d iffer ent leve ls 2/1 8/2 016 5:3 6:2 9P M CONTENTS 1 Carbon and its Compounds 2 Periodic Classification of Elements 38–63 3 How Do Organisms Reproduce? 64–91 4 Heredity and Evolution 5 Light: Reflection and Refraction 115–160 6 Human Eye and Colourful World 161–185 7 Our Environment 186–206 8 Management of Natural Resources 207–226 Objective Type Questions (Based Upon Practical Skills) 227–246 Answers for Self Assessments 247–254 Model Question Papers for Practice 1–37 92–114 M-1–M-10 Carbon and its Compounds (NCERT Textbook Chapter 4) 1.1 1.2 1.3 1.4 · Bonding in Carbon Versatile Nature of Carbon Chemical Properties of Carbon Compounds Soaps and Detergents Chemical bonds are the attractive forces which hold the atoms or ions together in a chemical species. The major reason of chemical bonding is the tendency of the atoms of the various elements to acquire stable configuration i.e. to complete their octet and to acquire a state of minimum energy. Noble gases are chemically less reactive gases and have eight electrons in their valence shells (except helium). Octet rule depicts the tendency of an atom of the element to have eight electrons in its valence shell. Chemical bonds are mainly of three types: ionic or electrovalent bond, covalent bond and coordinate bond. Covalent bond is the bond formed by equal contribution and mutual sharing of electrons between two atoms. The compounds containing covalent bonds are called covalent compounds. Covalency is the number of electrons contributed by an atom of the element for mutual sharing during the formation of a covalent bond. A pair of electrons shared between two atoms is called a bond pair of electrons. A pair of electrons present on one atom which does not take part in sharing is termed a lone pair of electrons. Single, double and triple covalent bonds are formed by the mutual sharing of one, two and three electron pairs respectively between two atoms. Organic compounds are made of C, H, O, N, S, P and halogens and have covalent bonds. Organic compounds have covalent bonds. They include hydrocarbons and their derivatives. Hydrocarbons are the organic compounds made up of carbon and hydrogen. Catenation is the property by the virtue of which atoms of the same element get linked together through covalent bonds so as to form long straight, branched or closed chains or rings. A carbon atom shows tetracovalency or tetravalency because it has four electrons in its valence shell. A large number of compounds are formed by carbon because of its tetravalency and the property of catenation. 1 MBD Super Refresher Science-X 2 Structural formula of a compound gives us the relative arrangements of bonded atoms in a molecule of it. An atom or a group of atoms which when present in a molecule gives certain special properties to the compound is called a functional group; e.g. – OH or alcoholic group, – CHO or aldehydic group. A Homologous series of compounds have compounds with the same functional group, and similar chemical properties. The successive members of a homologous series differ by CH2 unit and 14 mass units. IUPAC System stands for International Union of Pure and Applied Chemistry System. Saturated hydrocarbons are the hydrocarbons, which contain only single bonds between carbon atoms in their molecules. Unsaturated hydrocarbons are the hydrocarbons, which contain one or more double or triple bonds between carbon atoms in their molecules. Pyrolysis is the decomposition of higher molecular weight hydrocarbons into lower molecular weight hydrocarbons on heating at a high temperature in the absence of air. Compounds having same molecular formula but different properties are called isomers and this phenomenon is called isomerism. Carbon and its compounds come under the category of major source of fuels. Soaps and detergents are cleansing agents. Allotropy: It is the phenomenon of existence of an element in different forms having different physical properties but same or slightly different chemical properties. Soaps: These are sodium or potassium salts of higher fatty acids. Detergents: These are sodium alkyl benzene sulphonates. Saponification: It is the process of alkaline hydrolysis of fat to give soap and glycerol. Ester: Carboxylic acids react with alcohols to form esters and the reaction is known as esterification reaction. Absolute alcohol: Pure ethanol or ethanol with less than 1% water is called absolute alcohol. Denatured alcohol: It is made by adding poisonous substances such as copper sulphate or methanol to ethyl alcohol or ethanol. 1.1 Bonding in Carbon Carbon has four electrons in its valence shell and has a tendency to form four covalent bonds resulting in the formation of covalent compounds like methane (CH4), ethane (C2H6), acetic acid (CH3COOH) etc. These compounds are called organic compounds. Carbon forms covalent bonds with other C–atoms and some other elements such as H, O, S, N, F, Cl, Br or I. Carbon can form double or triple bonds (multiple bonds). NCERT Activity 1 – Page 58 Aim: To sort out the things made up of carbon compounds Carbon and its Compounds 3 Procedure: 1. Make a list of ten things you have used or consumed since morning. 2. Compile this list with the lists made by your classmates and then sort the items into the table given below. Things made of metal Things made of glass/clay Others Bucket Water Cooking pan Furniture Newspaper, books Soap Bread Cup (clay) Tea Medicine Observation: On observing the items listed in the last column of the table and consulting with the teacher, one can say that most of the items listed in this column are made up of carbon compounds. Conclusion: From this activity it can be concluded that most of the things that we use in our daily life are made up of carbon compounds. Objective Type Questions 1 mark each A. Answer the Following Questions 1. Which allotropic form of carbon is smooth as well as slippery? Answer: 1. Graphite B. Multiple Choice Questions 1. Which of the following crystalline forms of carbon has the composition C60 to C350? (a) Graphite (b) Fullerene (c) Diamond (d) Coal 2. Which among the following is an allotropic form of carbon? (a) Diamond (b) Graphite (c) Fullerene (d) All of these Answers: 1. (b) Fullerene 2. (d) All of these Short Answer Type Questions 2 – 3 marks each A. Describe the structure of Fullerene. Fullerenes are allotropes of carbon. The fullerene C60 has carbon atoms arranged in the form of a football and it looks like the geodesic dome designed by the US architect Buckminster Fuller. Thus, the molecule was named fullerene. MBD Super Refresher Science-X 4 B. Why do covalent molecules have definite shapes? A covalent bond is formed by the sharing of electrons between two atoms. The bonds are represented by dashes (—) and are directional in nature. The directional nature of the covalent bonds gives covalent molecules having two or more such bonds, a definite shape. This is also called definite geometry of the covalent molecule. C. Compare the structure of diamond and graphite and explain any one property of each based upon the structure. In diamond, each carbon atom is bonded to four other carbon atoms by covalent bonds resulting in the formation of a three-dimensional network structure. Due to the presence of strong covalent bonds, diamond is hard and has high melting point. In graphite each C–atom is bonded to three other carbon atoms to form hexagonal rings, which are held together by weak van der Waals’ forces of attraction. Therefore, graphite has a two-dimensional sheet-like structure. Due to the presence of one free electron left with each C–atom, graphite is a good conductor of electricity. Structure of graphite Structure of diamond 1.2 Versatile Nature of Carbon Carbon is a versatile element that forms the basis of all living organisms and many non-living objects. Carbon forms long linear chains, branched chains or rings with other C–atoms or functional groups. The ability of carbon to form chains gives rise to homologous series of compounds in which all the members contain the same functional group and show similar properties. The adjacent members of a homologous series differ by a CH2 unit. The names of organic compounds are written on the basis of IUPAC system. NCERT Activity 2 – Page 67 Aim: To calculate the difference in the formulae and molecular masses of (a) CH3OH and C2H5OH (b) C2H5OH and C3H7OH (c) C3H7OH and C4H9OH Calculations: (a) C2H5OH – CH3OH = CH2 (b) C3H7OH – C2H5OH = CH2 (c) C4H9OH – C3H7OH = CH2 Difference in molecular masses (a) [2 × 12 + 5 × 1 + 1 × 16 + 1 × 1] – [1 × 12 + 3 × 1 + 1 × 16 + 1 × 1] = 46 – 32 = 14 u Carbon and its Compounds 5 (b) [3 × 12 + 7 × 1 + 1 × 16 + 1 × 1] – [2 × 12 + 5 × 1 + 1 × 16 + 1 × 1] = 60 – 46 = 14 u (c) [4 × 12 + 9 × 1 + 1 × 16 + 1× 1] – [3 × 12 + 7 × 1 + 1 × 16 + 1 × 1] = 74 – 60 = 14 u Objective Type Questions Multiple Choice Questions 1. What is the functional group in HCHO? (a) Ketone (b) Aldehyde (c) Alcohol (d) Carboxylic acid 2. Butanone is a four-carbon compound with which functional group? (a) Carboxylic acid (b) Aldehyde (c) Ketone (d) Alcohol Answers: 1. (b) Aldehyde 2. (c) Ketone Short Answer Type Question 1 mark each 2 – 3 marks each A. What is a homologous series of compounds? List any two characteristics of a homologous series. A series of compounds having similar structural formulae, same functional group and hence similar chemical properties are called homologous series of compounds. Characteristics of homologous series: 1. The members of a homologous series have similar chemical properties. 2. Any two adjacent members of a homologous series differ by a CH2 unit in their molecular formulae. B. Give the functional group and their suffixes present in alkenes, alkynes and aldehydes. S. No. Homologous Series Functions Group Suffix C=C ene –C≡C– 1 Alkenes 2. Alkynes (Triple bond) yne 3. Aldehydes – CHO or al (Double bond) –C O H (Aldehydic group) Long Answer Type Question Give general formulae and IUPAC names of first two members of: 1. Monohydric alcohols 2. Haloalkanes 3. Monocarboxylic acids 4. Alkanones 5 marks each MBD Super Refresher Science-X 6 Also give their common names. S. No. 1. 2. 3. Homologons Series General Formula IUPAC names Methanol Common names CH3 – OH alcohols CnH2n + 1 – OH where (Alkanols) n = 1, 2, 3 C2H5 – OH or or R – OH Chloro- Methyl Monohydric Methyl alochol Ethanol Ethyl alcohol Haloalkanes CnH2n + 1 – X CH3 – CH2 – OH CH3 – Cl or where C2H5Cl methane chloride Alkyl halides n = 1, 2, 3 or Chloro- Ethyl X – F, Cl, Br, l CnH2n + 1 – COOH CH3 – CH2 – Cl H – COOH n = 0, 1, 2, 3 CH3 – COOH CnH2n + 1 – C – CH3 – C – CH3 ethane Methanoic acid Ethanoic acid Propanone chloride Formic acid Acedic acid Dimethyl ketone or Acetone Ethyl methyl Ketone Monocarbonxdic acid O 4. First two members Ketones (Alkanones) O CmH2m + 1 n = m simple ketone n ≠ m mixed ketone where n, m = 1, 2, 3 O CH3 – CH2 – C – CH3 Butanone 1.3 Chemical Properties of Carbon Compounds The important properties of carbon compounds are combustion, addition and substitution reactions. Carbon and its compounds are some of our major sources of fuels. Ethanol and ethanoic acid are the carbon compounds which are very important in our daily lives. NCERT Activity 3 – Page 69 Aim: To observe the nature of flame produced by burning naphthalene, camphor and alcohol Procedure: 1. Take some carbon compounds (naphthalene, camphor, alcohol) one by one on a spatula; burn them and observe the flame. Observation Table: Compound Alcohol Camphor Naphthalene Flame produced Non-luminous flame Smoky flame Smoky flame Deposition Carbon not deposited Carbon deposited Carbon deposited Conclusion: Alcohol produces non-luminous flame while camphor and naphthalene produce smoky flame. 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