Important Instructions for the School Principal. (Not to be printed with the question paper) Note:

Transcription

1 Important Instructions for the School Principal (Not to be printed with the question paper) ) This question paper is strictly meant for use in school based SA-I, September-202 only. This question paper is not to be used for any other purpose except mentioned above under any circumstances. 2) The intellectual material contained in the question paper is the exclusive property of Central Board of Secondary Education and no one including the user school is allowed to publish, print or convey (by any means) to any person not authorised by the board in this regard. ) The School Principal is responsible for the safe custody of the question paper or any other material sent by the Central Board of Secondary Education in connection with school based SA-I, September-202, in any form including the print-outs, compact-disc or any other electronic form. 4) Any violation of the terms and conditions mentioned above may result in the action criminal or civil under the applicable laws/byelaws against the offenders/defaulters. Note: Please ensure that these instructions are not printed with the question paper being administered to the examinees. Page of

2 I, 202 SUMMATIVE ASSESSMENT I, 202 / SCIENCE SC2-075 X / Class X 90 Time allowed : hours Maximum Marks : 90 (iii) (iv) (v) (vi) (vii) (viii) (ix) General Instructions : (iii) (iv) (v) (vi) (vii) (viii) (ix) The question paper comprises of two Sections, A and B. You are to attempt both the sections. All questions are compulsory. There is no overall choice. However, internal choice has been provided in all the five questions of five marks category. Only one option in such questions is to be attempted. All questions of Section-A and all questions of Section-B are to be attempted separately. Question numbers to in Section-A are one mark questions. These are to be answered in one word or in one sentence. Question numbers 4 to 7 in Sections-A are two marks questions. These are to be answered in about 0 words each. Question numbers 8 to 9 in Section-A are three marks questions. These are to be answered in about 50 words each. Question numbers 20 to 24 in Section-A are five marks questions. These are to be answered in about 70 words each. Question numbers 25 to 42 in Section-B are multiple choice questions based on practical skills. Each question is a one mark question. You are to select one most appropriate response out of the four provided to you. Page 2 of

3 SECTION-A Why are the magnetic field lines closed curves? Name the hormone secreted in boys at puberty. Why are the solar cookers painted black? 2 Calcium oxide reacts with water to give calcium hydroxide. Write the balanced chemical equation for the above reaction. Also identify the type of chemical reaction Name an ore of mercury. Why must metal sulphides and carbonates be converted into metal oxides prior to reduction? Define one volt. Draw symbols of the following components as used in circuit diagrams : electric bulb ammeter 2 2 Name and state the rule to determine the direction of a force experienced by a current carrying straight conductor placed in a magnetic field which is perpendicular to it. Name a device that uses current carrying conductor and magnetic field. 8. Fe 2 O 2Al Al 2 O 2Fe 2 PbO C 2Pb CO 2 Identify the substances that are oxidized and the substances that are reduced in the following reactions : Fe 2 O 2Al Al 2 O 2Fe 2 PbO C 2Pb CO 2 What is meant by redox reaction? Page of

4 9. State reasons for the following : Iron articles get coated with a reddish brown powder when left for sometime in open. Burning of coal is an exothermic reaction. The chemical equations should be balanced. 0. State one example of a synthetic indicator and an olfactory indicator? How do bacteria decay our teeth? Why do we basic tooth pastes for cleaning our teeth?. (NaCl) ( Na, Cl 7) Why do ionic compounds have high melting and boiling points? Show the formation of sodium chloride (NaCl) by the transfer of electrons (atomic number Na, Cl 7) V 0 A B. A hot plate of an electric oven, connected to a 220 V line. It has two resistance coils A and B each of 0 resistance which may be used separately, in series or in parallel. Find the value of the current required in each of the three cases. State reasons for the following : Tungsten is used for making bulb filaments Copper and aluminium are generally used for electricity transmission. Alloys are commonly used in electrical heating devices such as electric iron and toaster. 4. A.C. D.C. D.C. AC D.C A.C. State one main difference between A.C and D.C. Why A.C is preferred over D.C for long range transmission of electric power? Name one source each of D.C and A.C. Page 4 of

5 5. List two functions of stomata. Name the cells which control the opening and closing of stomata. How do they perform this function? 6. Name the plant hormone which is present in greater concentration in areas of rapid cell division. How is pea plant able to climb up other plants or fences? Explain. 7. Draw a neat diagram of a neuron. Label the following parts and state one function of each : dendrite axon 8. Name the process through which nuclear energy is generated. State two examples of elements which are used for nuclear energy generation. List any two reasons which make large scale use of nuclear energy prohibitive. 9. / State an advantage and a disadvantage of electricity generation through hydropower plant. Name two dams/projects which faced opposition over their construction from the local public State the need for refining of metals obtained by various reduction processes? Name any two metals which are refined by the process of electrolytic refining. Draw a labelled diagram showing electrolytic refining of any metal. Name the substances which are used for making anode cathode and the electrolyte during this process for a particular metal. OR Define an alloy. How is an alloy prepared? State one advantage of making alloys. Write the composition of stainless steel. Why is it preferred over iron? State two Page 5 of

6 reasons. 2. X X X X X / 5 A compound X is used in the kitchen for making crispy pakoras. Identify the compound and write its common name and chemical formula. Write the chemical equation of the process by which X is produced. What is the nature of compound X? State one use of X based on its nature. Name the powder or mixture obtained by mixing X with tartaric acid. Why is this mixture/powder added to cakes? OR Describe an activity to show that the crystals of copper sulphate contain water of crystallization. Write the formula of hydrated copper sulphate. Define water of crystallization. State two more examples of salts which have the water of crystallization State Ohm s law. Write the mathematical representation of Ohm s law. Use this relationship to define ohm. List two disadvantages of connecting different electrical appliances in series. OR SI 000 W, 220 V 2 ` 5.00 kwh 0 Define power. State the difference between watt and watt hour. Establish the relationship between unit of electric energy and SI unit of energy. An electric heater rated 000 W/ 220 V operates 2 hours daily. Calculate the cost of energy to operate for 0 ` 5.00 per kwh. 2. A.C / 5 Page 6 of

7 Write the values of the following physical quantities in connection with domestic power supply in our country potential difference between live wire and neutral wire frequency of A.C (iii) Explain the role of the following as safety measure in domestic electric appliances/circuits. earth wire fuse OR 24. What is a solenoid? The magnetic field lines inside a solenoid are in the form of equidistant parallel straight lines. What does this signify? How is electromagnet formed? Draw a diagram to show the field lines of the magnetic field through and around a current carrying solenoid. Draw a diagram of human digestive system and label the parts : where digested food is absorbed which secretes enzyme trypsin where digestion of starch starts through which food is taken to the stomach from mouth Name the end products formed due to digestion of proteins carbohydrates fats OR Draw a labelled diagram showing different steps of nutrition in amoeba. State one example of an organism that : Page 7 of

8 breaks down the food material outside the body and then absorb it. derive nutrition from plants or animals without killing them. SECTION-B The chemical reaction between barium chloride solution and sodium sulphate solution is an example of : decomposition reaction combination reaction displacement reaction double displacement reaction An iron nail was placed in a test tube containing aqueous copper sulphate solution. When the nail is taken out after about half an hour, its surface is coated with : greenish deposit white deposit reddish brown deposit black deposit 27. ph ph I II III IV ph / I II II III I, II, III, IV IV A student determined the ph of the given four samples using ph paper. Sodium bicarbonate Hydrochloric acid Lemon juice Distilled water I II III IV The ph paper will turn red/pink with the following : I and II only II and III only I, II, III, IV IV only 28. A ph A A few drops of a liquid A were added to distilled water. The water now turned ph paper blue. The liquid A is lemon juice sodium hydroxide solution common salt solution hydrochloric acid 29. HCl (A) NaOH (B) A B A Page 8 of

9 B A pinch of sodium carbonate was added to two test tubes one containing dil HCl (A) and the other containing dilute NaOH (B). The correct observation was A brown coloured gas liberated in test tube A A brown coloured gas liberated in test tube B A colourless gas liberated in test tube A A colourless gas liberated in test tube B 0. I, II, III IV I II II III III IV I IV Zinc granules are placed in each of the four solutions I, II, III and IV as shown : The colour change would be observed in : I and II (B) II and III III and IV I and IV. Uma took an aluminium strip and dipped it in freshly prepared ferrous sulphate solution taken in a test tube. After some time, she observed some changes. One of her correct observations is : The green solution remained green. A black coating deposited on the aluminium strip Page 9 of

10 A brown gas is evolved A colourless gas with smell of burning sulphur is evolved. 2. A, B, C D (V) (I) A B C D Four students A, B, C and D performed the experiment To study the dependence of potential difference (V) across a resistor on the current (I) passing through it and determine its resistance. They plotted the graph as shown below: The student who has plotted the correct graph is A B C D. 0.2 V 0. V 0.05 V 0.0 V The least count of the given voltmeter is : 0.2 V 0. V 0.05 V 0.0 V 4. V I X, Y Z Page 0 of

11 A student draws the following circuit diagram for the experiment To study the dependence of V on current (I) across a resistor. The parts labeled X, Y and Z in this diagram are respectively: a resistor, a voltmeter and an ammeter a voltmeter, a resistor and an ammeter an ammeter, a resistor and a voltmeter a resistor, an ammeter and a voltmeter 5. Q P 0.2 V 2 V 2.2 V.8 V A student is performing the experiment to determine the equivalent resistance of two resistors when connected in parallel. She observes that the voltmeter pointer is at point P when key is unplugged and the pointer is at Q when the key is plugged. The correct voltmeter reading is : 0.2 V 2 V 2.2 V.8 V 6. Choose the appropriate set of apparatus for performing the experiment for finding the equivalent resistance of two resistors when connected in series : voltmeter, two resistors, battery, ammeter, connecting wires Page of

12 ammeter, voltmeter, key, rheostat, two resistors battery, connecting wires key, rheostat, voltmeter, two resistors, connecting wires, battery ammeter, two resistors, key, voltmeter, connecting wires To make the leaves of a potted plant starch free, a student should keep plant in dark for one or two days boil the leaf in water boil the leaf in ethanol cover the plant with transparent polythene A water bath must be used to boil leaf in ethanol because : ethanol catches fire ethanol burns the leaf ethanol cannot dissolve chlorophyll the leaf is not destarched properly A drop of glycerine is used to prepare a temporary mount of leaf peel to show stomata so that : material may stick on the slide visibility of the material becomes clearer material is not attacked by the bacteria material may not get dried up 40. While preparing the temporary mount of leaf peel, the cover slip should be placed gently. Page 2 of

13 to avoid air bubbles for removal of excess stain to stain the leaf peel properly for spreading the material evenly 4. A, B, C D KOH, KOH, The correct labelling A, B, C and D respectively as shown in the given figure are : boiled seeds, water, KOH, conical flask KOH, germinating seeds, water, conical flask Sodium carbonate, germinating seeds, ethanol, conical flask Sodium chloride, dried seeds, water, conical flask 42. CO 2 A student performed the experiment to show that CO 2 is produced during respiration. The water did not rise in the bent tube even after one hour of experiment. The most valid reason is flask is not air tight coloured water is not taken in the beaker germinating seeds do not respire round bottom flask is not taken in place of flat bottom flask - o 0 o - Page of