Board Paper of Class 10 2013 Science - Solutions

• Question 1
  Which metal is not more active than magnesium?
  
  (a) Potassium
  
  (b) Calcium
  
  (c) Iron
  
  (d) Sodium VIEW SOLUTION

• Question 2
  Which metal blocks are used to prevent the corrosion in the steamer along with plates of iron in the sea water?
  
  (a) Nickel
  
  (b) Carbon
  
  (c) Magnesium or Zinc
  
  (d) Manganese VIEW SOLUTION

• Question 3
  Which of the following is used as a preservative in juice of fruits and jams?
  (a) SO₂
  
  (b) CO₂
  
  (c) NH₃
  
  (d) H₂ VIEW SOLUTION

• Question 4
  Which of the following non-metallic element possesses luster?
  
  (a) Iodine
  
  (b) Sulphur
  
  (c) Phosphorus
  
  (d) Carbon VIEW SOLUTION

• Question 5
  What is the chemical formula of Oleum?
  
  (a) H₂S₂O₃
  
  (b) H₂SO₃
  
  (c) H₂S₂O₇
  
  (d) H₂SO₄ VIEW SOLUTION

• Question 6
  Which process is important for osmoregulation?
  
  (a) Respiration
  
  (b) Circulation
  
  (c) Excretion
  
  (d) Nutrition VIEW SOLUTION

• Question 7
  Shown here is a part of a blood report,
  
  
  
  
  (Note: 'Reference Range' shows the range of normal values.)
  
  The amount of which of the blood components in the report shown above, indicates that something could be wrong in the body?
  
  (a) The platelet Count
  
  (b) The R. B. C. Count
  
  (c) The total W.B.C. Count
  
  (d) The blood haemoglobin levels VIEW SOLUTION

• Question 8
  Bowman's capsule possesses a mass of capillaries, which is known as?
  
  (a) Veins
  
  (b) Blood capillaries
  
  (c) Glomerulus
  
  (d) Arteries VIEW SOLUTION

• Question 9
  The diagram shows a plant, which has received light from one side only. Which characteristics is this plant showing?
  
  
  
  
  
  (a) Reproduction and nutrition
  
  (b) Growth and irritability (response)
  
  (c) Irritability (response) and reproduction
  
  (d) Excretion and growth VIEW SOLUTION

• Question 10
  Hypothalamus is a part of the _____________.
  
  (a) Fore brain
  
  (b) Cerebellum
  
  (c) Mid brain
  
  (d) Hind brain VIEW SOLUTION

• Question 11
  The setup shown here is to be used by a group of students to classify materials as conducting and non-conducting.
  The materials that they want to classify are as follows:

  Pencil Lead

  Wax

  Glass

  Paper

  Plastic

  Paper Clip

  Copper wire

  Aluminium Foil

  
  
  
  What is the very FIRST thing that they should do before starting to test any materials?
  
  (a) Without placing anything between the open leads, connect the circuit and check if the bulb lights up.
  (b) Check with a person working in the laboratory, whether the given materials are conductors.
  (c) Place a known insulator between the leads given and check if the bulb glows.
  (d) Place the items one by one between the open leads given and if the bulb glows then list them as conductors. VIEW SOLUTION

• Question 12
  Si is a _______.
  
  (a) insulator
  
  (b) semiconductor
  
  (c) alloy
  
  (d) conductor VIEW SOLUTION

• Question 13
  In volta’s electric cell which of the following energy, conversion takes place?
  
  (a) Electrical energy into chemical energy
  
  (b) Chemical energy into electrical energy
  
  (c) Chemical energy into heat energy
  
  (d) Heat energy into electrical energy VIEW SOLUTION

• Question 14
  15Ω, 10Ω and 5Ω resistors are connected in parallel. What is the equivalent resistor of this connection?
  
  (a) Less than 5Ω
  
  (b) more than 30Ω
  
  (c) 30Ω
  
  (d) more than 15Ω VIEW SOLUTION

• Question 15
  With the help of which law the direction of a magnetic field can be decided?
  
  (a) Fleming's left hand rule
  
  (b) Fleming's right hand rule
  
  (c) Right hand thumb rule
  
  (d) Faraday's law VIEW SOLUTION

• Question 16
  Red coloured wire coming out of electric board is known as ________
  
  (a) live wire
  
  (b) earthing wire
  
  (c) fuse wire
  
  (d) neutral wire VIEW SOLUTION

• Question 17
  What is the frequency of a 220 V AC?
  
  (a) 50 Hz
  
  (b) 220 Hz
  
  (c) Zero
  
  (d) 60 Hz VIEW SOLUTION

• Question 18
  The matter in the core region of the sun is in _____ state.
  
  (a) Plasma.
  
  (b) Liquid.
  
  (c) Gaseous.
  
  (d) Solid. VIEW SOLUTION

• Question 19
  According to astronomer Ptolemy what is in the centre of universe?
  
  (a) Earth
  
  (b) Milky way
  
  (c) Stars
  
  (d) Sun VIEW SOLUTION

• Question 20
  A 400 km thick, bright layer around the sun is known as________.
  
  (a) Photosphere
  
  (b) Chromosphere
  
  (c) Terrestrial
  
  (d) None of these VIEW SOLUTION

• Question 21
  What are shooting stars?
  
  (a) Stars
  
  (b) Meteors
  
  (c) Meteorites
  
  (d) Comets VIEW SOLUTION

• Question 22
  C₃H₈ is the molecular formula of which compound?
  
  (a) Propane
  
  (b) Ethane
  
  (c) Butane
  
  (d) Methane VIEW SOLUTION

• Question 23
  How many carbons are present in the mixture of hydrocarbon of natural gas?
  
  (a) 1 to 4
  
  (b) 1 to 3
  
  (c) 2 to 4
  
  (d) 1 to 2 VIEW SOLUTION

• Question 24
  What is a the matured form of coal?
  
  (a) Lignite
  
  (b) Bitumen
  
  (c) Anthracite
  
  (d) Peat VIEW SOLUTION

• Question 25
  Isomers are molecules that have the same molecular formula, but a different arrangement of the atoms in space. That excludes any different arrangements which are simply due to the molecule rotating as a whole, or rotating about particular bonds.
  
  Which of the following sets of molecules represent isomers?
  
  (a)
  
  (b)
  
  (c)
  
  (d) VIEW SOLUTION

• Question 26
  Which functional group is possessed by ketone?
  
  (a) > C = 0
  
  (b) – CHO
  
  (c) – COOH
  
  (d) – OH VIEW SOLUTION

• Question 27
  If one of the hydrogen atom of an alkane is displaced by hydroxyl group than which type of compound we get ?
  
  (a) Ketone
  
  (b) Ester
  
  (c) Alcohol
  
  (d) Aldehyde VIEW SOLUTION

• Question 28
  By burning ethanol in the air which type of flame is produced?
  
  (a) Colourless
  
  (b) Blue
  
  (c) Yellow
  
  (d) Red VIEW SOLUTION

• Question 29
  The filaments of certain algae break again and again and each part develops as individual algae, which type of process is this?
  
  (a) Fragmentation
  
  (b) Binary Fission
  
  (c) Multiple Fission
  
  (d) Budding VIEW SOLUTION

• Question 30
  In which disease do lesions in the mucus membrane of a urinogenital track and ulcers take place?
  
  (a) Genetical Harpis
  
  (b) AIDS
  
  (c) Syphilis
  
  (d) Gonorrhoea VIEW SOLUTION

• Question 31
  When will sex determination in human take place?
  
  (a) During fission of an unfertilised egg
  
  (b) When ovum is fertilized
  
  (c) During fertilisation
  
  (d) During sexual intercourse VIEW SOLUTION

• Question 32
  Where have the Homo sapiens originated from?
  
  (a) Philippines
  
  (b) Eurasia
  
  (c) Indonesia
  
  (d) Africa VIEW SOLUTION

• Question 33
  Which disease takes place when there is an increase of sugar in the blood and the urine?
  
  (a) Dwarfism
  
  (b) Diabetes
  
  (c) Goitre
  
  (d) Hyperthyroidism VIEW SOLUTION

• Question 34
  Carbon atoms form __________ bonds with other carbon atoms.
  
  (a) ionic
  
  (b) metallic
  
  (c) covalent
  
  (d) hydrogen VIEW SOLUTION

• Question 35
  4 × 10¹¹ nm =     ?     m.
  
  (a) 400
  
  (b) 40
  
  (c) 0.4
  
  (d) 4000 VIEW SOLUTION

• Question 36
  Goldsmiths often add another metal (usually copper) to pure gold while making ornaments. Which of these could be the possible reason?
  
  (a) to increase its melting point
  
  (b) to increase its hardness
  
  (c) to reduce its specific heat
  
  (d) to reduce its electrical conductivity VIEW SOLUTION

• Question 37
  How is the exact pH of an aqueous solution is measured?
  
  (a) Litmus paper
  
  (b) pH meter
  
  (c) Universal indicator
  
  (d) pH paper VIEW SOLUTION

• Question 38
  At which value of pH of the innerside of the mouth, decay, of teeth take place?
  
  (a) Higher than 3.5
  
  (b) Higher than 5.5
  
  (c) Lower than 5.5
  
  (d) Lower than 3.5 VIEW SOLUTION

• Question 39
  On which factor the types of acid, concentrated and dilute, acid, are based on?
  
  (a) On property
  
  (b) On ionisation
  
  (c) On quantity
  
  (d) (a) and (b) both VIEW SOLUTION

• Question 40
  In the human digestive system, the enzyme amylase is secreted by which organ?
  
  (a) The stomach
  
  (b) The salivary glands
  
  (c) The liver
  
  (d) The pancreas VIEW SOLUTION

• Question 41
  Which of the following is an example of non-biodegradable waste?
  
  (a) Paper
  
  (b) Fruits
  
  (c) Polythene
  
  (d) Vegetables VIEW SOLUTION

• Question 42
  Which wavelength of the harmful UV radiations is prevented by the Ozone layer from entering the earth's atmosphere?
  
  (a) 200 nm - 310 nm
  
  (b) 400 nm - 700 nm
  
  (c) 320 nm - 400 nm
  
  (d) More than 700 nm VIEW SOLUTION

• Question 43
  In which book are the names of endangered plant species published?
  
  (a) The yellow data book
  
  (b) The green data book
  
  (c) The red data book
  
  (d) The endangered species book VIEW SOLUTION

• Question 44
  Which type of source of air pollution, volcano is?
  
  (a) Artificial and natural
  
  (b) Artificial
  
  (c) Natural
  
  (d) Man made VIEW SOLUTION

• Question 45
  The absolute refractive index of any medium is always________.
  
  (a) 1
  
  (b) < 1
  
  (c) > 1
  
  (d) 0 VIEW SOLUTION

• Question 46
  Which of the lens with focal length 10 cm, 25 cm and 50 cm has maximum power?
  
  (a) 50 cm
  
  (b) 20 cm
  
  (c) 25 cm
  
  (d) 10 cm VIEW SOLUTION

• Question 47
  Which of the following are primary colours?
  
  (a) Red, Green, Blue
  
  (b) Red, Green, Violet
  
  (c) Yellow, Green, Blue
  
  (d) Red, Blue, Yellow VIEW SOLUTION

• Question 48
  Any three colours of light, which produce white light when combined with the correct intensity, are called PRIMARY COLOURS of light. (Red, Green and Blue) Colours produced by the addition of equal intensities of two primary colours of light are called SECONDARY COLOURS of light. (Yellow, Cyan and Magenta) Any two colours of light, which produce white when combined, are said to be COMPLEMENTARY' COLOURS of each other.
  
  Study the figure given here and answer the following question.
  Which of the following colours is a complementary colour of 'BLUE'?
  
  
  
  (a) Yellow
  
  (b) Magenta
  
  (c) Red
  
  (d) Cyan VIEW SOLUTION

• Question 49
  Which colour of light scatters maximum due to the atmosphere?
  
  (a) Red
  
  (b) Yellow
  
  (c) Green
  
  (d) Blue VIEW SOLUTION

• Question 50
  Which metal is used in thermometer?
  
  (a) Copper
  
  (b) Mercury
  
  (c) Sodium
  
  (d) Silver VIEW SOLUTION

• Question 51
  Write four improvements expected in the future due to nanotechnology.             [2]

  
  OR
   

  What is the future challenges using nano technology? VIEW SOLUTION

• Question 52
  If an electric bulb connected to a 220 V line draws ‘an electric current of 0.5 A then, what will be the resistance of the filament of the bulb?                 [2] VIEW SOLUTION

• Question 53
  What is neutralisation reaction? Write two neutralisation reactions.            [2] VIEW SOLUTION

• Question 54
  Explain the statement: Anthracite is more used than the bituminous coal.               [2]
   

  OR
   

  Write two differences between LPG and CNG. VIEW SOLUTION

• Question 55
  What is wild life? What is it’s importance?              [2] VIEW SOLUTION

• Question 56
  What is the solar system? Write the names of the planets of the solar system in sequence.             [2] VIEW SOLUTION

• Question 57
  What is the circulatory system? Write the names of the circulatory fluids and the material that they transport.            [2] VIEW SOLUTION

• Question 58
  Give scientific reason. It is advisable to use Iodine containing salt in daily food.               [2] VIEW SOLUTION

• Question 59
  In what way can the homologous organ give evidence for evolution?              [2]

  
  OR
   

  In what way analogous organs give evidence for evolution. VIEW SOLUTION

• Question 60
  What are global problems? Write the global problems which are faced by living organisms.            [2] VIEW SOLUTION

• Question 61
  Write three differences between Myopia and Hypermetropia.              [3] VIEW SOLUTION

• Question 62
  What precautions should be taken during the use of electricity?               [3]

  
  OR

  
  Write a short note on fuse. VIEW SOLUTION

• Question 63
  Describe Frasch's method of extraction of sulphur.              [3] VIEW SOLUTION

• Question 64
  Write the uses of condensation polymer and Addition polymer.              [3]
   

  OR

  
  Explain the fermentation reaction and its importance. VIEW SOLUTION

• Question 65
  What is artificial propagation in plants? Write the names of the methods used for artificial propagation in plants and the plants in which these methods are used.                   [3] VIEW SOLUTION

• Question 66
  Derive the formula for a spherical mirror $\frac{1}{\mathrm{f}}=\frac{1}{\mathrm{u}}+\frac{1}{\mathrm{v}}$             [5] VIEW SOLUTION

• Question 67
  Explain the extraction of iron by blast furnace.               [5]

  
  OR
   

  Explain the Hall-Heroult method to obtain aluminium from alumina by electrochemical reduction. VIEW SOLUTION

• Question 68
  Explain the respiratory system of human-beings.             [5]
   

  OR
   

  Draw a neat and labelled diagram of the digestive system of human beings. With the help of this diagram, describe the process of digestion of food in human-beings. VIEW SOLUTION