Oswaal CBSE Class 10 Science Question Bank 2022-2023 PDF

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VISIT @PROCBSE IN TELEGRAM TO GET FREE BOOKS  PRO CBSE EDUCATE EMPOWER EVOLVE @PROCBSE DISCLAIMER WE DON'T OWN CREDIT! WE ARE JUST FORWARDING THE MATERIAL WHICH ARE ALREADY AVAILABLE ON INTERNET. AND DON'T SUPPORT PIRACY IN ANYWAY. FOR MORE CHECK DMCA. JOIN US ON DIFFERENT PLATFORM CLICK TO VEIW / OPEN CONTACT US If you are rightful owner of any content posted here, and object to them being displayed or if you are one of representetives of Copyrights department then contact us at @procbsecontactbot  th 18 EDITION YEAR 2022-23 I SBN “978-93-5595-139-7” CENTRAL BOARD OF SYLLABUS SECONDARY EDUCATION COVERED DELHI PUBLISHED BY OSWAAL BOOKS & LEARNING PVT. LTD. COPYRIG HT RESERVED 1/11, Sahitya Kunj, M.G. Road, Agra - 282002, (UP) India BY THE PUBLISHERS All rights reserved. No part of this book may be reproduced, 1/1, Cambourne Business Centre stored in a retrieval system, Cambridge, Cambridgeshire or transmitted, in any form or CB 236DP, United kingdom by any means, without written permission from the publishers. The author and publisher will gladly receive information 0562-2857671 enabling them to rectify any error or omission in subsequent editions. [email protected] www.OswaalBooks.com D I SC L A IMER Oswaal Books has exercised due care and caution in collecting all the data before publishing this book. In spite of this, if any omission, inaccuracy or printing error occurs with regard to the data contained in this book, Oswaal Books will not be held responsible or liable. Oswaal Books will be grateful if you could point out any such error or offer your suggestions which will be of great help for other readers. Kindle Edition  TABLE OF CONTENTS l Latest CBSE Syllabus released on 21st April 2022 for Academic Year 2022-2023 (CBSE Cir. No. Acad 48/2022) 9 - 13 l Latest Term-I & Term-II Board Papers 2021-22 - Fully solved 15 - 32 l Latest Topper's Answers 2020 33 - 48 In each chapter, for better understanding, questions have been classified with the typology issued by CBSE as : R - Remembering, U - Understanding, A - Applying AE - Analyzing & Evaluating C - Creating 7. Control and Co-ordination 150 - 170 Unit I l Topic 1. Control and Co-ordination in Plants Chemical Substances : Nature and Behaviour l Topic 2. Control and Co-ordination in Animals 1. Chemical Reactions 1 - 18 8. Reproduction 171 - 201 l Topic 1. Chemical Reactions and Equations l Topic 1. Asexual Reproduction and l Topic 2. Types of Chemical Reactions, Vegetative Propagation l Topic 2. Sexual Reproduction in Plants –Corrosion and Rancidity l Topic 3. Reproduction in Human Beings 2. Acids, Bases and Salts 19 - 40 9. Heredity and Evolution 202 - 229 l Topic 1. Acids and Bases l Topic 1. Heredity and Mendel’s Contribution l Topic 2. Salts, Their Properties and Uses l Topic 2. Basic Concepts of Evolution * Evolution, Evolution and Classification and Evolution 3. Metals and Non-Metals 41 - 61 should not be equated with progress l Topic 1. Properties of Metals and Non-Metals Self Assessment Test - 2 230 - 231  l Topic 2. Ionic compounds, Metallurgy and Corrosion Unit III 4. Carbon Compounds 62 - 93 Natural Phenomena l Topic 1. Carbon and its properties, Homologous 10. Light – Reflection and Refraction 232 - 279 series and IUPAC Names l Topic 1. Reflection of Light, Image Formed by Spherical Mirrors l Topic 2. Ethanol, Ethanoic acid, l Topic 2. Refraction, Lenses and Power of Lens Soap and Detergents 11. Human Eye and The Colourful World 280 - 304 *5. Periodic Classification of Elements 94 - 118 l Topic 1. Human eye, Defects of vision l Topic 1. Periodic Laws and their Limitations and corrections l Topic 2. Refraction of Light through prism, l Topic 2. Periodic Elements and Periodic Properties Dispersion of Light and Scattering Self Assessment Test - 1 119 - 120 of Light  *Colour of sun at sunrise and sunset Unit II Self Assessment Test - 3 305 - 305  World of Living Unit IV 6. Life Processes 121 - 149 Effects of Current l Topic 1. Nutrition 12. Electricity 306 - 334 l Topic 2. Respiration l Topic 1. Electric Current, Ohm’s Law l Topic 3.Circulation and Transportation l Topic 2. Resistance in Series and Parallel Combination, Electric l Topic 4. Excretion Power and Heating Effect (3)  TABLE OF CONTENTS 13. Magnetic Effects of Electric Current 335 - 356 15. Our Environment 376 - 401 l Topic 1. Magnetic Effects l Topic 1. Ecosystem and Food Chain l Topic 2. Electric Generator and Electric Motor l Topic 2. Biodegradable and Non-Biodegradable *Electric Motor, *Electromagnetic induction, substances and Global Warming *Induced Current, *Fleming's Right Hand, *Electric Generator *16. Management of Natural Resources 402 - 420 Self Assessment Test - 4 357 - 358 l Topic 1. Natural Resources, Sustainable  Unit V Development and Biodiversity Natural Resources l Topic 2. Water Conservation and Fossil Fuels *14. Sources of Energy 359 - 375 Self Assessment Test - 5 421 - 422  l Topic 1. Conventional Sources of Energy qq l Topic 2. Alternative or Non-Conventional Sources of Energy *Kindly note that this Chapter/Topic has been deleted from the Latest CBSE Syllabus for Academic Year 2022-23. Hence it is optional to study it. (4)  LET THE ADVENTURE BEGIN! India is currently one of the youngest economies in the world. Hence, it’s imperative for our education system to churn out more learners than ever before. Considering the current learning mindset of students CBSE has recently introduced the curriculum The new way of learning; for classes IX to XII containing academic content, syllabus for Blended Learning examinations with learning outcomes, pedagogical practices and assessment guidelines. The Board will conduct the annual scheme The pandemic introduced us all of assessment at the end of the Academic session 2022-23 as per to a phenomenon which now the given curriculum. seems to be the way forward for learners & teachers alike, it is What Oswaal Question Banks have for you? blended learning. In just a span The structural changes in Education that are being brought in by of a year, we have witnessed a the latest Syllabus and the new National Educational Policy (NEP) rapid advancement in e-learning. resonate with our approach of focusing on deeper understanding Many researchers say that, in instead of rote learning. We have designed this book to make no time e-learning will become learning simpler for every student. Our cognitive and innovative mainstream. Oswaal Books exercises make us the leaders of simplified learning. Our study identified this as an opportunity material proves to be so effective because it is based on Bloom’s and thus we decided to prepare Taxonomy and also helps retain information for a longer period students for this turbulent yet a of time. The last year saw a sudden rise in the need for online classes and self-study. So as blended learning replaces traditional very useful change with Oswaal learning methods, Oswaal Books provides the right material to 360. Through Oswaal 360 we aim adapt and learn faster. This book takes an intuitive approach to help the students learn at their for skill development to unleash a student’s maximum potential. own pace. Hence, we wish to Questions like Tabular Based Questions, Passage Based Questions, make learning adaptive in order Picture Based Questions, Fill in the Blanks, Match the Following, to simplify it for every student. etc. have been exclusively developed by the Oswaal Editorial Board to help students master these new Typologies of Questions. Benefits of studying from Oswaal Question Banks Previous Years' Questions with Board Marking Scheme Answers Revision Notes for in-depth study Modified & Empowered Mind Maps & Mnemonics for quick learning Chapterwise learning Outcomes & Art integration as per NEP Include Questions from CBSE official Question Bank released in April 2021 Unitwise Self-Assessment Tests & Practice Papers Concept videos for blended learning Our Heartfelt Gratitude! We have taken due care in developing this book. There have been a lot of people who have helped us in our journey. We would like to offer heartfelt gratitude to them- our authors, editors, reviewers, and especially students like you who regularly send us suggestions which help us in continuous improvement of this book. Wish you all Happy Learning and a Successful Academic Year 2022-23!! (5) Get Unlimited Access to Free Resources at: oswaalbooks.com/free-resources/ How? It’s Easy as GET SET GO Step 1: Visit oswaalbooks.com/ free-resources/ and choose your board and class. Step 2: Not Registered? Register here quickly for the ocean of knowledge inside. (If registered already, simply login and move ahead) Step 3: You are here! Enjoy this unlimited treat of FREE resources. (6)  WISH TO KNOW WHAT WE HAVE FOR YOU UNDER FREE RESOURCES? HERE YOU GO: Date Sheet Latest Sample Question Paper Board Syllabus 2023 Exams Project Report Solved Board Paper 2019, 2020, 2021 Lab Activities (Science & Math only) Toppers’ Answers 2015 to 2020 Flowcharts & Mind Maps Where to report any plausible How to decode icons given content or technical error? throughout the book? Write to us on: [email protected] Topic-wise & Chapter-wise and remember to mention the following. Mnemonics Previous Years’ Board Papers Mind Maps Full name of the book with its ISBN Topper’s Answer Mention the page number and specify the error Concept Videos You may also upload an image with the error marked, with a little Highly Expected Questions detail of the error. for the upcoming exam (7)  CBSE CIRCULAR 2022-23 dsUæh; ek/;fed f'k{kk cksMZ CENTRAL BOARD OF SECONDARY EDUCATION CBSE/Acad/2022 April 21, 2022 Cir No Acad-48/2022 All Heads of Institutions affiliated to CBSE Subject : CBSE - Secondary and Senior School Curriculum 2022-23 1. CBSE annually provides curriculum for classes IX to XII containing academic content, syllabus for examinations with learning outcomes, pedagogical practices and assessment guidelines. 2. Considering the feedback of stakeholders and other prevailing conditions, the Board will conduct the annual scheme of assessment at the end of the Academic Session 2022-23 and the curriculum has been designed accordingly. Details are available at the link https://cbseacademic.nic.in/ curriculum_2023.html 3. It is important that schools ensure curriculum transaction as per the directions given in the initial pages of the curriculum document. The subjects should be taught as per the curriculum released by the Board with the help of suitable teaching-learning strategies such as Art-Integrated Education, Experiential Learning, and Pedagogical Plans etc. wherever possible. 4. Before making annual pedagogical plan to ensure curriculum transaction for optimal learning, it is desirable that the Head of the School may take a session with all the teachers on the important topics covered in initial pages of the curriculum document as well as the topics covered under subject-wise syllabus. 5. Sample Question Papers with detailed design of the Question Paper will be made available on CBSE’s website in due course of time. 6. Schools are requested to share the curriculum available on https://cbseacademic.nic.in/ curriculum_2023.html including initial pages to all the teachers and students. With Best wishes, (Dr. Joseph Emmanuel) Director (Academics) (8)  SYLLABUS Science Class - X (Code No. 086) Latest Syllabus issued by CBSE for Academic Year 2022-23 (Annual Examination) 3 Hours Marks 80 Unit No. Unit Marks I Chemical Substances – Nature and Behaviour 25 II World of Living 23 III Natural Phenomena 12 IV Effects of Current 13 V Natural Resources 07 Total 80 Internal Assessment 20 Grand Total 100 Theme : Materials (55 Periods) Unit I : Chemical Substances - Nature and Behaviour Chemical Reactions : Chemical equation, Balanced chemical equation, implications of a balanced chemical equation, types of chemical reactions: combination, decomposition, displacement, double displacement, precipitation, endothermic exothermic reactions, oxidation and reduction. Acids, bases and salts : Their definitions in terms of furnishing of H+ and OH– ions, General properties, examples and uses, neutralization, concept of pH scale (Definition relating to logarithm not required), importance of pH in everyday life; preparation and uses of Sodium Hydroxide, Bleaching powder, Baking soda, Washing soda and Plaster of Paris. Metals and non-metals : Properties of metals and non-metals; Reactivity series; Formation and properties of ionic compounds; Basic metallurgical processes; Corrosion and its prevention. 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 hydro carbons 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. Theme : The World of the Living (50 Periods) Unit II : World of Living Life processes : ‘Living Being’. Basic concept of nutrition, respiration, transport and excretion in plants and animals. (9)  SYLLABUS Control and co-ordination in animals and plants : Tropic movements in plants; Introduction of plant hormones; Control and co-ordination in animals: Nervous system; Voluntary, involuntary and reflex action; Chemical co-ordination: animal hormones. 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: (topics excluded - evolution; evolution and classification and evolution should not be equated with progress). 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 re- quired); 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 (exclud- ing colour of the sun at sunrise and sunset). Theme : How Things Work (32 Periods) Unit IV : Effects of Current Electric current, potential difference and electric current. Ohm’s law; Resistance, Resistivity, Factors on which the resistance of a conductor depends. Series combination of resistors, parallel combination of re- sistors and its applications in daily life. Heating effect of electric current and its applications in daily life. Electric power, Interrelation between P, V, I and R. Magnetic effects of current : Magnetic field, field lines, field due to a current carrying conductor, field due to current carrying coil or solenoid; Force on current carrying conductor, Fleming’s Left Hand Rule, Direct current. Alternating current: frequency of AC. Advantage of AC over DC. Domestic electric circuits. Theme : Natural Resources (20 Periods) Unit V : Natural Resources Our environment: Eco-system, Environmental problems, Ozone depletion, waste production and their solutions. Biodegradable and non-biodegradable substances. Note for the Teachers: 1. The chapter Management of Natural Resources (NCERT Chapter 16) will not be assessed in the year-end examination. However, learners may be assigned to read this chapter and encouraged to prepare a brief write up to any concept of this chapter in their Portfolio. This may be for Internal Assessment and credit may be given Periodic Assessment/Portfolio). ( 10 )  SYLLABUS 2. The NCERT text books present information in boxes across the book. These help students to get concep- tual clarity. However, the information in these boxes would not be assessed in the year-end examination. PRACTICALS Practical should be conducted alongside the concepts taught in theory classes LIST OF EXPERIMENTS 1. A. Finding the pH of the following samples by using pH paper/universal indicator: Unit-I (i) Dilute Hydrochloric acid (ii) Dilute NaOH solution (iii) Dilute Ethanoic Acid solution (iv) Lemon juice (v) Water (vi) Dilute Hydrogen carbonate solution. B. Studying the properties of acids and bases (HCl & NaOH) on the basis of their reaction with: Unit-I a. Litmus solution (Blue/Red) b. Zinc metal c. Solid sodium carbonate 2. Performing and observing the following reactions and classifying them into: Unit-I a. Combination reaction b. Decomposition reaction c. Displacement reaction d. Double displacement reaction (i) Action of water on quick lime. (ii) Action of heat on ferrous sulphate crystals. (iii) Iron nails kept in copper sulphate solution. (iv) Reaction between sodium sulphate and barium chloride solutions. 3. Observing the action of Zn, Fe, Cu and Al metals on the following salt solutions: Unit-I (i) ZnSO4 (aq) (iii) FeSO4 (aq) (ii) CuSO4(aq) (iv) Al2 (SO4)3 (aq) Arranging Zn, Fe, Cu and Al (metals) in the decreasing order of reactivity based on the above result. 4. Studying the dependence of potential difference (V) across a resistor on the current (I) passing through it and determine its resistance. Also plotting a graph between V and I. Unit-IV 5. Determination of the equivalent resistance of two resistors when connected in series and parallel. Unit-IV 6. Preparing a temporary mount of a leaf peel to show stomata. Unit- II 7. Experimentally show that carbon dioxide is given out during respiration. Unit-II 8. Study of the following properties of acetic acid (ethanoic acid): Unit- I ( 11 )  SYLLABUS (i) odour (ii) solubility in water (iii) effect on litmus (iv) reaction with sodium Hydrogen Carbonate 9. Study of the comparative cleaning capacity of a sample of soap in soft and hard water. Unit- I 10. Determination of the focal length of: Unit-III (i) Concave mirror (ii) Convex lens by obtaining the image of a distant object. 11. Tracing 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. Unit - III 12. Studying (a) binary fission in Amoeba, and (b) budding in yeast and Hydra with the help of prepared slides. Unit-II 13. Tracing the path of the rays of light through a glass prism. Unit-III 14. Identification of the different parts of an embryo of a dicot seed (Pea, gram or red kidney bean). Unit-II Prescribed Books Science-Textbook for class IX-NCERT Publication  Science-Text book for class X- NCERT Publication  Assessment of Practical Skills in Science-Class IX - CBSE Publication  Assessment of Practical Skills in Science- Class X- CBSE Publication  Laboratory Manual-Science-Class IX, NCERT Publication  Laboratory Manual-Science-Class X, NCERT Publication  Exemplar Problems Class IX – NCERT Publication  Exemplar Problems Class X – NCERT Publication   ( 12 )  SYLLABUS Question Paper Design (Class X) Science (086) Theory (80 marks) Competencies Total Demonstrate Knowledge and Understanding 46% Application of Knowledge/Concepts 22% Formulate, Analyze, Evaluate and Create 32% 100% Note: Typology of Questions: VSA including objective type questions, Assertion – Reasoning type  questions; SA; LA; Source-based/ Case-based/ Passage-based/ Integrated assessment questions. An internal choice of approximately 33% would be provided.  Internal Assessment (20 Marks) Periodic Assessment - 05 marks + 05 marks  Subject Enrichment (Practical Work) - 05 marks  Portfolio - 05 marks  Suggestive verbs for various competencies Demonstrate Knowledge and Understanding  State, name, list, identify, define, suggest, describe, outline, summarise, etc. Application of Knowledge/Concepts  Calculate, illustrate, show, adapt, explain, distinguish, etc. Analyse, Evaluate and Create  Interpret, analyse, compare, contrast, examine, evaluate, discuss, construct, etc. ( 13 )  HOW TO USE THIS BOOK? Chapter Navigation Tools Chapter Mind Maps Syllabus Analysis Get Concept Clarity Prescribed by CBSE Know what’s important from the examination point of view Latest Topic-wise Revision Typology of Segregation Notes Questions For Focused Study Chapter Summary Passage/ Picture/ Developed by Oswaal Visual & MCQs Editorial Board based questions Find Exam Oriented Preparation Tools in the Chapter Commonly Mnemonics QR Codes Made Errors Test To help you avoid some Self Assessment Memorising Better For Concept Videos common errors in your (Unit-wise) answers Sample Question Papers Previous Answering Topper’s Academically Years’ Board Tips Answer Important Papers Look out for Highly Tips to Improve Learn how to write To help you decode Expected Questions for your Score perfect answers the paper pattern the upcoming exams ( 14 ) CBSE SAMPLE QUESTION PAPER (TERM-II) 2021-22 [ 15 Sample Question Paper, 2021-22 (Issued by CBSE Board on 14th January 2022) SCIENCE (Term-II) SOLVED General Instructions : (i) All questions are compulsory. (ii) The question paper has three sections and 15 questions. (iii) Section–A has 7 questions of 2 marks each; Section–B has 6 questions of 3 marks each; and Section–C has 2 case based questions of 4 marks each. (iv) Internal choices have been provided in some questions. A student has to attempt only one of the alternatives in such questions. It was observed that in field A, the offsprings showed Section - A only the parental trait for consecutive generations, 1. The table shows the electronic structures of four whereas in field B, majority of the offsprings showed elements. a variation in the progeny. What are the probable reasons for these? Element P Q R S OR Electronic 2, 6 2, 8, 1 2, 8, 7 2, 8, 8 In an asexually reproducing species, if a trait X exists Structure in 5% of a population and trait Y exists in 70% of the (a) Identify which element(s) will form covalent same population, which of the two traits is likely to bonds with carbon. have arisen earlier? Give reason. (b) “Carbon reacts with an element in the above 6. A simple motor is made in a school laboratory. A coil table to form several compounds.” Give suitable of wire is mounted on an axle between the poles of a reason. horseshoe magnet, as illustrated. 2. The diagram below shows part of the periodic table. (a) Which elements would react together to form covalent compounds? (b) Between the two elements W and Z, which will have a bigger atomic radius? Why? 3. (a) Trace the path a male gamete takes to fertilise a female gamete after being released from the penis. In the example above, coil ABCD is horizontal and (b) State the number of sets of chromosomes present the battery is connected as shown. in a zygote. (a) For this position, state the direction of the force 4. Rajesh observed a patch of greenish black powdery on the arm AB. mass on a stale piece of bread. (b) Why does the current in the arm BC not (a) Name the organism responsible for this and its contribute to the turning force on the coil? specific mode of asexual reproduction. OR (b) Name its vegetative and reproductive parts. A circuit contains a battery, a variable resistor 5. Mustard was growing in two fields- A and B, while and a solenoid. The figure below shows the field A produced brown coloured seeds, field B magnetic field pattern produced by the current produced yellow coloured seeds. in the solenoid. 16 ] Oswaal CBSE Chapterwise & Topicwise Question Bank, SCIENCE, Class – X A carbon compound ‘A’ having melting point 156K and boiling point 351K, with molecular formula C2H6O is soluble in water in all proportions. (a) Identify ‘A’ and draw its electron dot structure. (b) Give the molecular formulae of any two homologous of ‘A’. 10. Two pea plants-one with round yellow (RRYY) seeds and another with wrinkled green (rryy) seeds (a) State how the magnetic field pattern indicates produce F1 progeny that have round, yellow (RrYy) seeds. regions, where the magnetic field is stronger. (b) What happens to the magnetic field when the When F1 plants are self-pollinated, which new current in the circuit is reversed? combination of characters is expected in F2 progeny? 7. DDT was sprayed in a lake to regulate breeding of How many seeds with these new combinations of mosquitoes. How would it affect the trophic levels characters will be produced when a total of 160 seeds in the following food chain associated with a lake? are produced in F2 generation? Explain with reason. Justify your answer. 11. (a) It would cost a man `3.50 to buy 1.0 kW h of electrical energy from the Main Electricity Board. His generator has a maximum power of 2.0 kW. The generator produces energy at this maximum power for 3 hours. Calculate how much it would cost to buy the same amount of energy from the Main Electricity Board. (b) A student boils water in an electric kettle for 20 OR minutes. Using the same mains supply, he wants In the following food chain, vertical arrows indicate to reduce the boiling time of water. To do so, should he increase or decrease the length of the the energy lost to the environment and horizontal arrows indicate the energy transferred to the next heating element? Justify your answer. trophic level. Which one of the three vertical arrows 12. (A, C and E) and which one of the two horizontal arrows (B and D) will represent more energy transfer? Give reason for your answer. In the above circuit, if the current reading in the ammeter A is 2A, what would be the value of R1? OR Section - B 8. Choose an element from period 3 of modern periodic table that matches the description given below in each instance. Give reason for your choice. (a) It has a similar structure to diamond. Calculate the total resistance of the circuit and find (b) It has same valency as Lithium. the total current in the circuit. (c) It has variable valency and is a member of the 13. Gas A, found in the upper layers of the atmosphere, Oxygen family (group 16). is a deadly poison but is essential for all living beings. 9. (a) How many isomers are possible for the The amount of this gas started declining sharply in compound with the molecular formula C4H8? the 1980's. Draw electron dot structure of branched chain (a) Identify Gas A. How is it formed at higher levels isomer. of the atmosphere? (b) How will you prove that C4H8 and C5H10 are (b) Why is it essential for all living beings? State the homologous? cause for the depletion of this gas. OR CBSE SAMPLE QUESTION PAPER (TERM-II) 2021-22 [ 17 Section - C This section has 02 case-based questions (14 and 15). Each case is followed by 03 sub-questions (a), (b), (c). Parts (a) and (b) are compulsory. However, an internal choice has been provided in part (c). 14. Sahil performed an experiment to study the inheritance pattern of genes. He crossed tall pea plants (TT) with short pea plants (tt) and obtained all tall plants in F1 generation. (a) What set of genes will be present in the F1 A magnet is attached to a spring. The magnet can go generation? in and out of the stationary coil. (b) Give reason, why only tall plants are observed He lifted the magnet and released it to make it oscillate in F1 progeny. through the coil. Based on your understanding of the phenomenon, answer the following questions. (c) When F1 plants were self - pollinated, a total of (a) What is the principle which Ansari Sir is trying 800 plants were produced. How many of these to demonstrate? would be tall, medium height or short plants? (b) What will be observed when the magnet starts Give the genotype of F2 generation. oscillating through the coil. Explain the reason OR behind this observation. When F1 plants were cross-pollinated with plants (c) Consider the situation where the magnet goes having tt genes, a total of 800 plants were produced. in and out of the coil. State two changes which could be made to increase the deflection in the How many of these would be tall, medium, or short galvanometer. plants? Give the genotype of F2 generation. OR 15. Ansari Sir was demonstrating an experiment in his Is there any difference in the observations in the class with the setup as shown in the figure below. galvanometer when the magnet swings in and then out of the stationary coil? Justify your answer. qqq Marking Scheme Answers 2021-22 (Issued by CBSE) (b) Zygote has 2 sets of chromosomes. 1 Section - A 4. (a) The greenish black powdery mass on a stale 1. (a) P and R ½+½ piece of bread is due to bread mould (Rhizopus) (b) Carbon has a valency of four or tetravalency & which reproduces by spore formation. ½ + ½ catenation ½+½ (b) Hyphae or thread like structures are the vegetative part and tiny blob like structures or 2. (a) Y and Z 1 sporangia are the reproductive parts. ½ + ½ (b) W has bigger atomic radius. ½ In field A, the reason for parental trait in consecutive 5. Reason: generations of the offsprings is self-pollination. 1 Down the group, number of shells increases. In field B, variation is seen because of recombination ½ of genes as cross-pollination is taking place. 1 3. (a) Male gamete (sperm) travels in the female OR reproductive tract after being released. The Trait Y, which exists in 70% (larger fraction) of the path which it takes to fertilise the female population, is likely to have arisen earlier because gamete (egg) is vagina, uterus, fallopian tube in asexual reproduction, identical, copies of DNA where it fuses with the egg cell resulting in the are produced and variations do not occur. 1 formation of a zygote (Alternative: labelled figure of human female New traits come in the population due to sudden reproductive system indicating the passage mutation and then are inherited. 70 % of the of sperm from vagina to uterus and then to population with trait Y is likely to have been fallopian tube for fertilisation, resulting in the replicating that trait for a longer period, than 5 % formation of a zygote.) 1 of population with trait X. 1  18 ] Oswaal CBSE Chapterwise & Topicwise Question Bank, SCIENCE, Class – X 6. (a) downwards 1 (b) Sodium (b) Because BC is in the same direction as the Reason: It has 1 valence electron like Lithium direction of field lines. Force is minimum when ½+½ the direction of current in the conductor is the (c) Sulphur same as that of the magnetic field. BC will not Reason: It forms oxides SO2 and SO3 ½+½ contribute as the force on this part of the coil 9. (a) Five 1½ will be cancelled by the force on DA. 1 OR (a) Relative closeness of field lines indicates the strength of magnetic field. Since, field lines are crowded around the ends of the solenoid, hence these are the regions of strongest magnetism. 1 (b) The direction of the field will also be reversed. 1 (b) C4H8 and C5H10 are homologous ½ 7. l DDT being a non-biodegradable pesticide will as they differ in enter the food chain from the first trophic level l “–CH2–” i.e., Plankton. ½ l differ in 14u molecular mass l Non-biodegradable pesticides accumulate l Same functional group progressively at each trophic level. This l Same general formula ½+½ phenomenon is known as biological (Any two reasons) magnification. 1 OR l Hawk will have the highest level of pesticide. (a) Ethanol; C2H5OH 1+1 ½ OR A will represent more energy transfer as compared to C and E. ½ B will represent more energy transfer as compared to D. ½ ethanol When green plants are eaten by primary (b) CH3OH and C3H7OH are homologous of ethanol. 1 consumers, a great amount of energy is lost OR as heat in to the environment, some amount CH4O and C3H8O 1 goes into digestion and in doing work and the 10. Round green: 30 ½+½ rest goes towards growth and reproduction. Wrinkled yellow: 30 ½+½ An average of 10% of the food eaten is made New combinations are produced because of the available for the next level of consumers. This independent inheritance of seed shape and seed loss of energy takes place at every trophic colour trait. 1 level. 1 11. (a) E = P × T (Alternatively accept- In accordance with 10% So, E = 3 × 2 = 6 kWh 1 Cost of buying electricity from the main law of transfer of energy in a food chain, only electricity board = 6 x 3.50 = `21.0 10% of energy available at one trophic level is (b) To reduce the boiling time using the same transferred to the next trophic level.) mains supply, the rate of heat production should be large. We know that P = V2/R. Since Section - B V is constant, R should be decreased. Since R is directly proportional to L so, length should be 8. (a) Silicon decreased. 2 Reason: Tetrahedral structure 12. 5 ohm, 10 ohm and R1 are in parallel connection OR 1/Rp = 1/5 + 1/10 + 1/R1 Tetravalency or four valeny and catenation 1/Rp = (2+1)/10 + 1/R1 = 3/10 + 1/R1 OR 1/Rp = (3R1 + 10)/10R1 Covalent bonding like carbon ½+½ CBSE SAMPLE QUESTION PAPER (TERM-II) 2021-22 [ 19 Rp = 10R1/(3R1 + 10) 13. (a) Gas A is Ozone. ½ Now, 6 ohm, 6 ohm and Rp are in series Ozone at the higher levels of the atmosphere Thus, is a product of UV radiation acting on Req = 12 + 10 R1/(3R1 + 10)....(i) 1 oxygen (O2) molecule. The higher energy UV radiations split apart some molecular oxygen V = I Req (O2) into free oxygen (O) atoms. These atoms From the circuit then combine with molecular oxygen to form Req = 30/2 = 15 Ω...(ii) 1 ozone. 1 Equating (i) and (ii) UV 12 + 10 R1/(3R1 + 10) = 15 O2 —® O + O 10R1/(3R1 + 10) = 3 O + O2 ® O 3 10R1 = (9R1 + 30) (b) Ozone shields the surface of the earth and Thus, R1 = 30 ohm. 1 protects living organisms from ultraviolet (UV) radiations released by the sun. ½ OR Chlorofluorocarbons (CFC's) which are used as refrigerants in fire extinguishers lead to depletion of ozone layer. ½+½ Section - C 14. (a) Tt 1 (b) Both the recessive and dominant trait are passed on in F1 progeny. Out of the two trait only one of them is able to express itself in the progeny, which is called the dominant (T), while the other one is called the recessive (t). Here, the ‘tall’ trait is the dominant one. 1 (c) Out of 800 plants, 600 plants will be tall and 200 plants will be small. 1:2:1 (TT:Tt:tt) 1+1 OR In the cross between Tt X tt, 400 Tall (Tt) and 400 short (tt) plants will be produced. 1 1:1(Tt:tt) 1 15. (a) Sir is trying to demonstrate the principle of Electromagnetic induction. 1 (b) There will be fluctuating induced current in the coil due to relative motion between the magnet and the coil. Accordingly the galvanometer needle will fluctuate on either side of 0 mark. Changing the magnetic field around the coil generates induced current. 1 (c) Using a stronger magnet, or using a coil with more number of turns. 2 OR When the magnet moves into the coil, the R3 and R4 are in series, hence the equivalent galvanometer shows a momentary deflection resistance of those two = R5 = R3 + R4 = 10 ohm. ½ towards one side, say left. ½ R5 and R2 are in parallel, Let R6 be the equivalent When the magnet moves out of the coil, the resistance for them. Hence, R6 = (R5R2)/(R5 + R2) = galvanometer shows a momentary deflection 100/20 = 5 ohm ½ now towards right. ½ Now R1 and R6 are in series and hence the final This is due to changing magnetic field /flux equivalent resistance of the entire circuit is R = R1 + associated with the coil as the magnet moves R6 = 12 ohm. 1 in and out. Alternatively, the flux increases when the By Ohm's Law, we know that V = IR, hence I = V/R. magnet goes in and it decreases when the Hence the current in the circuit is 24/12 A = 2A 1 magnet goes out. 1 nnn  Solved Paper, 2021-22 SCIENCE Term-I, Set-4 Question Paper Series : JSK/2 Code No. 031/2/4 Time allowed : 90 Minutes Max. Marks : 40 General Instructions : (i) This question paper contains 60 questions out of which 50 questions are to be attempted. All questions carry equal marks.  (ii) The question paper consists three sections – Section A, B and C.  (iii) Section–A consists of 24 questions. Attempt any 20 questions from Q. No. 1 to 24. (iv) Section–B also consists of 24 questions. Attempt any 20 questions from Q. No. 25 to 48. (v) Section–C consists of three Case Studies containing 12 questions and 4 questions in each case. Attempt any 10 from Q. No. 49 to 60. (vi) There is only one correct option for every Multiple Choice Question (MCQ). Marks will not be awarded for answering more than one option. (vii) There is no negative marking. (a) Carbon dioxide which extinguishes the burning candle. SECTION-A (b) Oxygen due to which the candle burns more Section-A consists of 24 questions (Q. No. 1 to 24). Attempt brightly. any 20 questions from this section. The first attempted (c) Sulphur dioxide which produces a suffocating 20 questions would be evaluated. smell. 1. A student took sodium sulphate solution in a test (d) Hydrogen which while burning produces a tube and added barium chloride solution to it. He popping sound. observed that an insoluble substance has formed. 4. Sodium reacts with water to form sodium hydroxide The colour and molecular formula of the insoluble and hydrogen gas. The balanced equation which substance is: represents the above reaction is; (a) Grey, Ba2SO4 (b) Yellow, Ba(SO4)2 (a) Na(s) + 2H2O(l) → 2NaOH(aq) + 2H2(g) (c) White, BaSO4 (d) Pink, BaSO4 (b) 2Na(s) + 2H2O(l) → 2NaOH(aq) + H2(g) 2. Which of the following oxide(s) is/are soluble in water (c) 2Na(s) + 2H2O(l) → NaOH(aq) + 2H2(g) to form alkalies? (d) 2Na(s) + H2O(l) → 2NaOH(aq) + 2H2(g) (i) Na2O (ii) SO2 5. Which of the options in the given table are correct? (iii) K2O (iv) NO2 (a) (i) and (iii) (b) (i) only Option Natural Source Acid Present (c) (ii) and (iv) (d) (iii) only (i) Orange Oxalic acid 3. Study the diagram given below and identify the gas formed in the reaction. (ii) Sour milk Lactic acid (iii) Ant sting Methanoic acid (iv) Tamarind Acetic acid Dilute (a) (i) and (ii) (b) (i) and (iv) sulphuric acid (c) (ii) and (iii) (d) (iii) and (iv) 6. C6H12O6(aq) + 6O2(aq) → 6CO2(aq) + 6H2O(l) Zinc granules The above reaction is a/an (a) displacement reaction (b) endothermic reaction (c) exothermic reaction (d) neutralisation reaction SOLVED PAPER - 2021-22 (TERM-I) [ 21 7. Which of the following statements about the reaction The correct statements are given below are correct? (a) (i) and (ii) only (b) (ii) and (iii) only MnO2 + 4HCl → MnCl2 + 2H2O + Cl2 (c) (ii), (iii) and (iv) (d) (i), (ii) and (iii) (i) HCl is oxidized to Cl2 12. In living organisms during respiration which of (ii) MnO2 is reduced to MnCl2 the following products are not formed if oxygen is (iii) MnCl2 acts as an oxidizing agent not available? (iv) HCl acts as on oxidizing agent (a) Carbon dioxide + Water (a) (ii), (iii) and (iv) (b) (i), (ii) and (iii) (c) (i) and (ii) only (d) (iii) and (iv) only (b) Carbon dioxide + Alcohol 8. Select from the flowing the statement which is true (c) Lactic acid + Alcohol for bases. (d) Carbon dioxide + Lactic Acid (a) Bases are bitter and turn blue litmus red. 13. The correct statements with references to single (b) Bases have a pH less than 7. celled organisms are (c) Bases are sour and change red litmus to blue. (i) Complex substances are not broken down into (d) Bases turn pink when a drop of phenolphthalein simpler substances. is added to them. (ii) Simple diffusion is sufficient to meet the 9. Study the following table and choose the correct requirements of exchange of gases. option: (iii) Specialised tissues perform different functions in Salt Parent Parent Nature of the organism. Acid Base Salt (iv) Entire surface of the organism is in contact with the environment for taking in food. (a) Sodium HCl NaOH Basic Chloride (a) (i) and (iii) (b) (ii) and (iii) (c) (ii) and (iv) (d) (i) and (iv) (b) Sodium H2CO3 NaOH Neutral 14. Which one among the following is not removed as a Carbonate waste product from the body of a plant? (c) Sodium H2SO4 NaOH Acidic (a) Resins and Gums (b) Urea Sulphate (c) Dry Leaves (d) Excess Water (d) Sodium CH3COOH NaOH Basic 15. Which of the following statements are correct Acetate in reference to the role of A (shown in the given 10. It is important to balance the chemical equations to diagram) during a breathing cycle in human beings? satisfy the law of conservation of mass. Which of the following statements of the law is incorrect? (a) The total mass of the elements present in the reactants is equal to the total mass of the elements present in the products. (b) The number of atoms of each element reamains the same, before and after a chemical reaction. (c) The chemical coomposition of the reactants is the same before and after the reaction. (d) Mass can neither be created nor can it be destroyed in a chemical reaction. 11. Consider the following statements in connection (i) It helps to decrease the residual volume of air in with the functions of the blood vessels marked A and lungs. B in the diagram of a human heart as shown. (ii) It flattens as we inhale. A (iii) It gets raised as we inhale. (iv) It helps the chest cavity to become larger. B (a) (ii) and (iv) (b) (iii) and (iv) (c) (i) and (ii) (d) (i), (ii) and (iv) 16. Which one of the following conditions is true for the state of stomata of a green leaf shown in the given diagram? (i) Blood vessel A – It carries carbon dioxide rich blood to the lungs. (ii) Blood vessel B – It carries oxygen rich blood from the lungs. (iii) Blood vessel B – Left atrium relaxes as it receives blood from this blood vessel. (iv) Blood vessel A – Right atrium has thick muscular wall as it has to pump blood to this blood vessel.  22 ] Oswaal CBSE Chapterwise & Topicwise Question Bank, SCIENCE, Class – X (a) Large amount of water flows into the guard cells. (b) Gaseous exchange is occurring in large amount. (a) Concave mirror (b) Concave lens (c) Large amount of water flows out from the guard (c) Convex mirror cells. (d) Convex lens (d) Large amount of sugar collects in the guard cells. 20. A ray of light starting from air passes through 17. In which of the following is a concave mirror used? medium A of refractive index 1.50, enters medium (a) A solar cooker B of refractive index 1.33 and finally enters medium (b) A rear view mirror in vehicles C of refractive index 2.42. If this ray emerges out in (c) A safety mirror in shopping malls air from C, then for which of the following pairs of media the bending of light is least? (d) In viewing full size image of distant tall buildings (a) air-A (b) A-B 18. A student wants to obtain magnified image of an (c) B-C (d) C-air object AB as on a screen. Which one of the following 21. Which of the following statements is not true for arrangements shows the correct position of AB for scattering of light? him/her to be successful? (a) Colour of the scattered light depends on the size M A of particles of the atmosphere. (b) Red light is least scattered in the atmosphere. B O (c) Scattering of light takes place as various colours (a) 2F1 F1 of white light travel with different speed in air. C1 (d) The fine particles in the atmospheric air scatter the blue light more strongly than red. So the N scattered blue light enters our eyes. M 22. For the diagram shown, according to the new Cartesian sign convention the magnification of the image formed will have the following specifications: O I (b) I II 2F1 I II F1 A I III IIIIIIIIIIIIIIIIIII N P C F O III III (a) Sign – Positive, Value – Less than 1 (c) (b) Sign – Positive, Value – More than 1 (c) Sign – Negative, Value – Less than 1 (d) Sign – Negative, Value – More than 1 23. A ray of light is incident as shown. If A, B and C are three different transparent media, then which among the following options is true for the given diagram? (d) A 1 B 23 C 4 19. The following diagram shows the use of an optical device to perform an experiment of light. As per the arrangement shown, the optical device is likely to be (a) ∠1 > ∠4 (b) ∠1 < ∠2 a; (c) ∠3 = ∠2 (d) ∠3 > ∠4 24. In the diagram given below, X and Y are the end colours of the spectrum of white light. The colour of 'Y' represents the SOLVED PAPER - 2021-22 (TERM-I) [ 23 (a) Colour of sky as seen from earth during the day. Q (b) Colour of the sky as seen from the moon. Dilute Calcium (c) Colour used to paint the danger signals. hydrochloric hydroxide (d) Colour of sun at the time of noon. acid solution P SECTION-B Section-B consists of 24 questions (Q. No. 25 to 48). Attempt 28. Which one of the following structures correctly any 20 questions from this section. The first attempted depicts the compound CaCl2? 20 questions would be evaluated. 2– 2+ 25. Which one of the following reactions is categorised as (a) Ca 2+ [ Cl [ × (b) [ Ca [ [ Cl [ × × × × × × × × × 2 (d) [ Ca [ [ Cl [ 2+ – thermal decomposition reaction? (c) Ca 2+ [ Cl [ × × × × × × × × (a) 2H2O(l) → 2H2(g) + O2(g) 2 × × 2 (b) 2AgBr(s) → 2Ag(s) + Br2(g) 29. The pair(s) which will show displacement reaction is/ are (c) 2AgCl(s) → 2Ag(s) + Cl2(g) (i) NaCl solution and copper metal (d) CaCO3(s) → CaO(s) + CO2(g) (ii) AgNO3 solution and copper metal 26. Consider the pH value of the following acidic (iii) Al2(SO4)3 solution and magensium metal samples: (iv) ZnSO4 solution and iron metal (a) (ii) only (b) (ii) and (iii) S.No. Sample pH Value (c) (iii) and (iv) (d) (i) and (ii) 30. Which of the following salts do not have the water of 1. Lemon Juice 2.2 crystallisation? (i) Bleaching Powder (ii) Plaster of Paris 2. Gastric Juice 1.2 (iii) Washing soda (iv) Baking soda (a) (ii) and (iv) (b) (i) and (iii) 3. Vinegar 3.76 (c) (ii) and (iii) (d) (i) and (iv) 4. Dil. Acetic acid 3.0 Question No. 31-35 consists of two statements – Assertion (A) and Reason (R). Answer these questions selecting the + appropriate option given below: The decreasing order of their H ion concentration is (a) Both (A) and (R) are true and (R) is the correct (a) 3 > 4 > 1 > 2 (b) 2 > 1 > 3 > 4 explanation of (A). (c) 2 > 1 > 4 > 3 (d) 3 > 4 > 2 > 1 (b) Both (A) and (R) are true but (R) is not the correct explanation of (A). 27. Study the experimental set up shown in given figure (c) (A) is true but (R) is false. and choose the correct option from the following: (d) (A) is false but (R) is true. P Q Change observed in 31. Assertion (A) : Sodium hydrogen carbonate is used as an ingredient in antacids. calcium hydroxide solution Reason (R) : NaHCO3 is a mild non-corrosive basic salt. (a) K2CO3 Cl2 gas No change 32. Assertion (A) : Burning of natural gas is an (b) KHCO3 CO2 No change endothermic process. gas Reason (R) : Methane gas combines with oxygen to produce carbon dioxide and water. (c) KHCO3 H2 gas Turns milky 33. Assertion (A) : Nitrogen is an essential element for (d) K2CO3 CO2 Turns milky plant growth and is taken up by plants in the form of gas inorganic nitrates or nitrites. Reason (R) : The soil is the nearest and richest source of raw materials like Nitrogen, Phosphorus and other minerals for the plants.  24 ] Oswaal CBSE Chapterwise & Topicwise Question Bank, SCIENCE, Class – X 34. Assertion (A) : Sun appears reddish at the time of (a) Percentage of carbon dioxide is more in inhaled Sunrise and Sunset. air. Reason (R) : Distance travelled by sunlight in the (b) Fermentation occurs in the presence of oxygen. atmosphere is lesser during sunrise and sunset as (c) Percentage of carbon dioxide is more in the compared to noon. exhaled air. 35. Assertion (A) : Hydrochloric acid helps in the (d) Fermentation occurs in the presence of carbon digestion of food in the stomach. dioxide. Reason (R) : Hydrochloric acid creates an acidic medium to activate protein digesting enzymes. 39. If a lens can converge the sun rays at a point 20 cm, 36. A student was asked to write a stepwise procedure away from its optical centre, the power of this lens is to demonstrate that carbon dioxide is necessary for (a) +2D (b) –2D photosynthesis. He wrote the following steps. The (c) +5D (d) –5D wrongly worded step is: 40. The radius of curvature of a converging mirror is 30 cm. At what distance from the mirror should an object be placed as to obtain a virtual image? (a) Infinity Green (b) 30 cm Plant