8th Class Science Chemical Effects of Electric Current Question Bank

done Chemical Effects of Current and Light Total Questions - 40

• question_answer1)
  Which one of the following is a weak electrolyte?
  A)
  \[HCl\]solution                done clear
  B)
  Citric acid solution done clear
  C)
  Na OH solution done clear
  D)
         \[Cu\,S{{O}_{4}}\]solution done clear
  E)
  None of these done clear
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• question_answer2)
  A bulb placed in the electric circuit in the given experimental set-up does not glow because:
  A)
  The liquid used in the above experiment may be a strong electrolyte. done clear
  B)
  The liquid used in the above experiment may not be conducting electricity. done clear
  C)
  The bulb may be fused done clear
  D)
  Both [b] and [c] done clear
  E)
  None of these done clear
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• question_answer3)
  LED refers to:
  A)
  Light emitting diode done clear
  B)
  Light electrolyte diode done clear
  C)
  Less electrolyte demand done clear
  D)
  Light electrolyte demand done clear
  E)
  None of these done clear
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• question_answer4)
  Which one of the following is correct pair?
  A)
  Cathode - Positive electrode done clear
  B)
  Anode - Negative electrode done clear
  C)
  Cation - Negative ion done clear
  D)
  Anion - Positive ion done clear
  E)
  None of these done clear
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• question_answer5)
  In electrolysis, salt solution breaks up into positively and negatively ? charged particles are called:
  A)
  Electrodes                      done clear
  B)
  Electrons done clear
  C)
  Ions                  done clear
  D)
  Insulators done clear
  E)
  None of these done clear
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• question_answer6)
  Two plane mirrors MN and NO are kept at right angle to each other as shown in the given figure. A ray of light CD is incident on the mirror MN and the angle of incidence is\[{{50}^{o}}\]. What will be the angle of reflection for the mirror NO.
  A)
  \[{{50}^{o}}\]                         done clear
  B)
  \[{{60}^{o}}\] done clear
  C)
  \[{{30}^{o}}\]                         done clear
  D)
  \[{{40}^{o}}\] done clear
  E)
  None of these done clear
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• question_answer7)
  Galvanization involves the coating of which metal over steel or iron?
  A)
  Chromium                     done clear
  B)
  Copper done clear
  C)
  Zinc                  done clear
  D)
  Brick done clear
  E)
  None of these done clear
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• question_answer8)
  Which of the following is correct for electroplating a metal X with copper through electrolyses?
  A)
  Metal X-Anode done clear
  B)
  Copper-Cathode done clear
  C)
  Copper sulphate solution ? Electrolyte done clear
  D)
  All the above done clear
  E)
  None of these done clear
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• question_answer9)
  Choose the correct option for the given figure.
  A)
  (a - incident ray), (b - normal ray), (c - reflected ray), (d - angle of incidence) done clear
  B)
  (a - reflected ray), (b - incident ray), (c - normal ray), (d -angle of reflection) done clear
  C)
  (a - incident ray), (b - normal ray), (c - reflected ray), (d - angle of reflection) done clear
  D)
  (a - angle of incidence), (b - normal ray), (c - reflected ray), (d - incident ray) done clear
  E)
  None of these done clear
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• question_answer10)
  The process of depositing a thin layer of desired metal over a metal object with the help of electric current is called?
  A)
  Combination                  done clear
  B)
  Electroplating done clear
  C)
  Electrolysis                     done clear
  D)
  All the above done clear
  E)
  None of these done clear
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• question_answer11)
  When a ray of light falls normally on a plane mirror, then the angle of incidence is:
  A)
  \[{{30}^{o}}\]                         done clear
  B)
  \[{{0}^{o}}\] done clear
  C)
  \[{{180}^{o}}\]                       done clear
  D)
  \[{{60}^{o}}\] done clear
  E)
  None of these done clear
  View Solution play_arrow

• question_answer12)
  On which of the following surfaces diffused reflection will not take place
  A)
  Paper done clear
  B)
  Plane mirror done clear
  C)
  Cardboard done clear
  D)
  Unpolished metal object done clear
  E)
  None of these done clear
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• question_answer13)
  Look at the following figure and choose the correct option.
  A)
  X represents anode, Y represents cathode done clear
  B)
  X represents cathode, Y represents anode done clear
  C)
  Both represent anode done clear
  D)
  Both represent cathode done clear
  E)
  None of these done clear
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• question_answer14)
  Which one of the following is an effect produced by electric current?
  A)
  Heating effect     done clear
  B)
  Chemical effect done clear
  C)
  Magnetic effect done clear
  D)
         All the above done clear
  E)
  None of these done clear
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• question_answer15)
  Electrode connected to negative terminal of the battery is a/an:
  A)
  Electrolyte                      done clear
  B)
  Anode done clear
  C)
  Cathode done clear
  D)
  Cell done clear
  E)
  None of these done clear
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• question_answer16)
  _____ is an apparatus used to produce a thin beam of light.
  A)
  Microscope                     done clear
  B)
  Telescope done clear
  C)
  Ray-box            done clear
  D)
  Pin-hole camera done clear
  E)
  None of these done clear
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• question_answer17)
  Image formed by a plane mirror is:
  A)
  Real                              done clear
  B)
  In front of the mirror done clear
  C)
  Diminished                     done clear
  D)
  Laterally inverted done clear
  E)
  None of these done clear
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• question_answer18)
  Raman is standing at a distance of 2.5m from a plane mirror, how far he would be from his image?
  A)
  2.5m                 done clear
  B)
  5m done clear
  C)
  3m                                done clear
  D)
  1m done clear
  E)
  None of these done clear
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• question_answer19)
  To purify copper metal by electrolysis which of the following is used as electrolyte
  A)
  \[NaCl\]solution  done clear
  B)
  \[CuS{{O}_{4}}\]solution done clear
  C)
  \[{{H}_{2}}S{{O}_{4}}\]solution done clear
  D)
         \[MgS{{O}_{4}}\]solution done clear
  E)
  None of these done clear
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• question_answer20)
  ____ is used in a periscope for the reflection of light.
  A)
  Concave lens                  done clear
  B)
  Convex lens done clear
  C)
  Concave mirror   done clear
  D)
  Plane mirror done clear
  E)
  None of these done clear
  View Solution play_arrow

• question_answer21)
  What will be the number of images formed when two plane mirrors are kept inclined at an angle of\[{{60}^{o}}\].
  A)
  4                                  done clear
  B)
  5 done clear
  C)
  10                                 done clear
  D)
  3 done clear
  E)
  None of these done clear
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• question_answer22)
  Hole present at the center of iris called:
  A)
  Retina               done clear
  B)
  Blind spot done clear
  C)
  Pupil                 done clear
  D)
         Eye lens done clear
  E)
  None of these done clear
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• question_answer23)
  Which of the following solutions will not make the bulb glow placed in an electric circuit?
  A)
  Sulphuric acid solution done clear
  B)
  Sodium chloride solution done clear
  C)
  Silver nitrate done clear
  D)
  Sugar solution in diluted water done clear
  E)
  None of these done clear
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• question_answer24)
  Which one of the following observations can be observed when electric current is passed through an electrolyte in which two electrodes are present?
  A)
  Bubbles of gas may be formed on the electrodes. done clear
  B)
  Deposits of metal may be seen on electrodes. done clear
  C)
  Change in the colour of the solution may take place. done clear
  D)
  All the above done clear
  E)
  None of these done clear
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• question_answer25)
  Radhika is standing at a distance of 10 cm from the plane mirror, how far should she move so that the distance between her and her image will become 10 cm.
  A)
  10 cm towards the mirror. done clear
  B)
  5 cm away from the mirror. done clear
  C)
  5 cm towards the mirror. done clear
  D)
  10 cm away from the mirror. done clear
  E)
  None of these done clear
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• question_answer26)
  In electroplating the metal on which electroplating is to be done is made the:
  A)
  Anode               done clear
  B)
  Cathode done clear
  C)
  Electrolyte                      done clear
  D)
  Electric cell done clear
  E)
  None of these done clear
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• question_answer27)
  Hypermetropia can be corrected by using:
  A)
  Concave lens      done clear
  B)
  Convex lens done clear
  C)
  Concave mirror done clear
  D)
  Concavo - convex lens done clear
  E)
  None of these done clear
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• question_answer28)
  ___ metal is mostly used for electroplating on car parts, bicycle-handlebars to give them a shiny appearance.
  A)
  Iron                               done clear
  B)
  Copper done clear
  C)
  Chromium                     done clear
  D)
  Aluminum done clear
  E)
  None of these done clear
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• question_answer29)
  Which gas is produced at anode when current passes through acidified water?
  A)
  Hydrogen                       done clear
  B)
  Oxygen done clear
  C)
  Nitrogen             done clear
  D)
  Fluorine done clear
  E)
  None of these done clear
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• question_answer30)
  Human eye-lens is a:
  A)
  Concave lens      done clear
  B)
  Convex lens done clear
  C)
  Concavo - Convex lens done clear
  D)
  Convexo - Concave lens done clear
  E)
  None of these done clear
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• question_answer31)
  Which one of the following is an application of chemical effect of current?
  A)
  Electroplating done clear
  B)
  Purification of metals done clear
  C)
  Decomposing chemical compounds done clear
  D)
  All the above done clear
  E)
  None of these done clear
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• question_answer32)
  ____ effect of electric current is indicated by change in colour of a solution by passing electric current through it.
  A)
  Physical             done clear
  B)
  Chemical done clear
  C)
  Heating done clear
  D)
  Magnetic done clear
  E)
  None of these done clear
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• question_answer33)
  Rajan wants to deposit a layer of silver metal on a steel spoon then match the following according to the above statement.

  Column A		Column B
  (i)	Silver	[A]	Cathode
  (ii)	Steel	[B]	Electroplating
  (iii)	Silver cyanide solutions	[C]	Anode
  (iv)	Process	[D]	Electrolyte

  A)
  (i-C), (ii-D), (iii-B), (iv-A) done clear
  B)
  (i-C), (ii-A), (iii-D), (iv-B) done clear
  C)
  (i-A), (ii-C), (m-D), (iv-B) done clear
  D)
  (i-A), (ii-B), (iii-C), (iv-D) done clear
  E)
  None of these done clear
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• question_answer34)
  Number of images formed is three when two plane mirrors are inclined at angle of:
  A)
  (a)\[{{60}^{o}}\]                                 done clear
  B)
  \[{{30}^{o}}\] done clear
  C)
  \[{{90}^{o}}\] done clear
  D)
  \[{{25}^{o}}\] done clear
  E)
  None of these done clear
  View Solution play_arrow

• question_answer35)
  An instrument which works by producing multiple reflections from plane mirrors and forms beautiful patterns is:
  A)
  Periscope                       done clear
  B)
  Telescope done clear
  C)
  Kaleidoscope      done clear
  D)
  Pinhole camera done clear
  E)
  None of these done clear
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• question_answer36)
  Which one of the following eye parts can change the focal length of the eye-lens according to the requirements of the eye to see distant objects or nearby objects?
  A)
  Retina               done clear
  B)
  Ciliary muscles done clear
  C)
  Pupil                             done clear
  D)
  Cornea done clear
  E)
  None of these done clear
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• question_answer37)
  ____ is the screen on which the image is formed in the eye.
  A)
  Iris                                done clear
  B)
  Pupil done clear
  C)
  Retina               done clear
  D)
  Eye-lens done clear
  E)
  None of these done clear
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• question_answer38)
  Glowing of bulb when current passes through it is an example of:
  A)
  Chemical effect of electric current. done clear
  B)
  Heating effect of electric current. done clear
  C)
  Magnetic effect of electric current. done clear
  D)
  All the above done clear
  E)
  None of these done clear
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• question_answer39)
  ______ adjusts the size of ____ according to the intensity of light received by the eye from the surroundings.
  A)
  Retina, pupil                   done clear
  B)
  Iris, retina done clear
  C)
  Iris, pupil           done clear
  D)
  Pupil, Iris done clear
  E)
  None of these done clear
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• question_answer40)
  Which one of the following statements is correct?
  A)
  Anvil is a part of human eye. done clear
  B)
  Space between cornea and eye-lens is filled with aqueous humour. done clear
  C)
  Space between eye-lens and retina is filled with vitreous humour. done clear
  D)
  Both [b] and [c] done clear
  E)
  None of these done clear
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