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Chemistry Past Questions and Answers

Waec Chemistry Questions

Question 21:
The following are uses of radioactive isotops except for
  • A Sterilization of medical equipment
  • B Tracing reaction paths
  • C Dating elements
  • D Radiography
  • E Determining equilibrum positions
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Question 22:
The main characteristic feature of transition metals is that they
  • A Have the same atomic size
  • B Are reducing agents
  • C From ions easily
  • D Have variable oxidation states
  • E Are highly electropositive
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Question 23:
The following are heavy chemicals except
  • A Tetraoxosulphate (IV) acid
  • B Caustic soda
  • C Sodium trioxocarbonate (IV)
  • D Ethene
  • E Dyes
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Question 24:
What quantity of silver is deposited when 96500C of electricity is passed through a solution containing silver ions? (Ag = 108, 1F = 96500C)
  • A 1.08g
  • B 40g
  • C 10,.8g
  • D 21.6g
  • E 108g
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Question 25:
Bubbling of carbon (IV)oxide into calcium hydroxide solution results in the formation of
  • A CaCO3
  • B CuCO3
  • C ZnCO,sub>3
  • D Na2CO3
  • E MgCO3
View Answer & Explanation