CBSE Class 10th Board Paper 2019 Science

CBSE Class 10th Board Paper 2019ScienceTime – 3 HoursM. Marks- 80General Instruction1. The question paper comprises of 5 sections A,B, C, D, E. You are to attempt all thesections.2. All Questions are compulsory.3. Internal choices in the sections B C D and E4. Question number 1 and 2 carry 1 mark and should be answered in one word or onesentence.5. Question number 3 to 5 carry 2 marks. These should be answered in 30 words each6. Question number 6 to 15 in section C carry 3 marks and should be answered in 50 wordseach7. Question number 16 to 21 in section D carry 5 marks each and should be answered in 70words each8. Question number 22 to 27 in section E are practical questions and carry 2 marks each.Section AQ1. If you could use any source of energy forheating your food which one would youprefer? State one reason of your choice.Q2. Write the function of voltmeter in anelectric circuitSection BQ3. What happens to the image distance inthe normal human eye when we decrease thedistance of an object, say 10 m to 1 m? Justifyyour answer.Q4. List two different functions performed bypancreas in our body.Q5. How can it be proved that the basicstructure of the Modern Periodic Table isbased on the electronic configuration ofatoms of different elements.ORThe electronic configuration of an element is2, 8, 4. State its:a. Group and Period in the ModernPeriodic Tableb. Name and write its one physicalpropertySection CQ6. How can we help in reducing the problemof waste disposal? State any 3 methodsORDefine Ecosystem. Draw a Block diagram toshow the flow of energy in an ecosystemDownload Solution to this Board Question Paper at https://logicalpaper.co

CBSE Class 10th Board Paper 2019ScienceQ7. List 3 advantages of:a. Exploiting resources with short termaims and]b. Using a long term perspective inmanaging our natural resources.Q8. What is a rainbow? Draw a labeleddiagram to show the formation of a rainbow.Q9. Nervous and Hormonal systems togetherperform the function of control andcoordination in human beings. Justify thisstatement with the help of an example.Q10. Trace the sequence of the events whichoccur when a bright light is focused in youreyes.Q11. What is Photosynthesis? Explain itsmechanism.Q12. Name the plant Mendel used for hisexperiment. What type of progeny wasobtained by Mendel in F1 and F2 generationswhen he crossed the tall and short plants?Write the ratio he obtained in F2 generationplants.ORList two differences between acquired traitsand inherited traits by giving an example ofeach.Q13. 2g of silver chloride is taken in a chinadish and the china dish is placed in sunlightfor sometime. What will be your observationin this case? Write the chemical reactioninvolved in the form of a balanced chemicalequation. Identify the type of chemicalequation.ORIdentify the type of reactions taking place ineach of the following cases and write thechemical equation for the reactions.a. Zinc reacts with silver nitrate toproduce zinc nitrate and silverb. Potassium iodode reacts with leadnitrate to produce potassium nitrateand lead iodide.Q14. Based on the group valency of elements,write the molecular formula of the followingcompunds giving justification for each:i.ii.iii.Oxide of first group elementsHalide of the elements of group 13andCompound formed when anelement A of group 2 combineswith an element B of group 17.Q15. Explain the followinga. Sodium Chloride is an ioniccompound which does not conductelectricity in solid state whereas itdoes conduct electricity in the moltenstate as well as in aqueous solution.b. Reactivity of aluminium decrease if itis dipped in nitric acid.c. Metals like calcium and magnesiumare never found in their free state innature.Section DQ16.a. With the help of a suitable circuitdiagram, prove that the reciprocal ofthe equivalent resistance of a group ofDownload Solution to this Board Question Paper at https://logicalpaper.co

CBSE Class 10th Board Paper 2019Scienceresistances joined in parallel is equalto the sum of the reciprocals of theindividual resistances.b. In an electric circuit, two resistors of12 Ω each are joined in parallel to a 6v battery. Find the current drawnfrom the battery.ORAs an electric lamp of resistance 20 Ω and aconductor of resistance 4 Ω are connected toa 6 V battery as shown in the circuit.Calculate:magnetic field is to be determined ismoved away from the straight wirecarrying constant current? Justifyyour answer.Q18. An object is placed at a distance of 60cmfrom a concave lens of focal length 30 cm.i.ii.iii.Use lens formula to find thedistance of the image from thelens.List four characterstics of theimage ( nature, position, size,erect/inverted) formed by thelens in this case.Draw ray diagram to justify youranswer of part (ii)Q19. Define pollination. Explain the differenttypes of pollination. List two agents ofpollination? How does suitable pollinationlead to fertilization?ORa. The total resistance of the circuitb. The current through the circuitc. The potential difference across thei.The electric lampii.Conductord. The power of the lampa. Identify the given diagram, Name thepart 1 to 5Q17.A. Draw magnetic field lines producedaround a current carrying straightconductor passing through acardboard. Name, state and apply therule to mark the direction of thesefield lines.B. How will the strength of the magneticfield change when the point whereb. What is contraception List 3advantages of adopting contraceptivemeasures.Download Solution to this Board Question Paper at https://logicalpaper.co

CBSE Class 10th Board Paper 2019ScienceQ20. Write the chemical formula and thename of the compound which is the activeingredient of all the alcoholic drinks. List itstwo uses. Write the chemical equation andthe name of the product formed when thiscompound reacts withi.ii.What is methane? Draw its electron dotstructure. Name the types of bonds formed inthis compound. Why are such compunds:Poor conductors of electricityHave low melting and boilingpoints What happens when thiscompound burns in oxygen?Q21.Write the main difference between anacid and a base. With the help of suitableexamples explain the term neutralization andthe formation ofi.ii.iii.ORDraw labelled diagram in proper sequence toshow budding in hydra.Sodium metalHot concentrated sulphuric acidORi.ii.Draw labelled diagram of the structure ofstomata as seen under the microscope.AcidicBasicNeutral saltsSection EQ22. In the experiment set up to show that“CO2 is given out during respiration”, namethe substance taken in small test tube kept inthe conical flask. State the function and theconsequence of its use.Q23. A student is observing the temporarymount of a leaf peel under a microscope.Q24. List four precautions which a studentshould observe while determining the focallength of the given convex lens by obtainingimage of a distant object on a screen.Q25. While studying the dependence of thepotential difference (V) across a resistor onthe current (I) passing through it, in order todetermine the resistance of the resisitor, astudent took 5 readings for different values ofcurrent and plotted a graph between V and I.He got a straight line graph passing thorughthe origin. What does the straight line signify?Write the method of determining resistanceof the resistor using the graph.ORWhat would you suggest to a student if whilepreparing an experiment he finds that thepointer/needle of the ammeter and voltmeteris available in the laboratory?Q26. In three test tubes, A,B,C three differentliquids namely, distilled water, undergroundwater and distilled water with a pinch ofcalcium sulphate is dissolved, respectively aretaken. Equal amount of soap solution is addedto each test tube and the contents are shaken.,in which test tube will the length of foam(lather) be longest? Justify your answerDownload Solution to this Board Question Paper at https://logicalpaper.co

CBSE Class 10th Board Paper 2019ScienceQ27. Blue Litmus solution is added to two testtubes A and B containing dilute HCl and NaOHsolution respectively. In which test tube acolor image will be observed? State the colorchange and give its reason.ORWhat is observed when 2 ml of dilute solutionof HCl is added to 1 g of sodium carbonatetaken in a clean and dry test tube? Write thechemical equation for the reaction involved.Buy Detailed Solution ToCBSE Science Board Paper 2019BUY NOWDownload Solution to this Board Question Paper at https://logicalpaper.co

CBSE Class 10th Board Paper 2019 Science Download Solution to this Board Question Paper at https://logicalpaper.co Section A Q1. If you could use any source of energy for heating your food which one would you prefer? State one reason of your choice. Q2. Write the function of voltmeter in an electric circuit Section B Q3.