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Chemistry Past Questions and Answers

Waec Chemistry Questions

Question 171:
Which of the reactions represented by the following equations will take place at room temperature?
  • A C 6 H2O → CO + H2
  • B CuO + H2 → Cu + H2O
  • C N2 + 3H2 → 2NH3
  • D 2Na + 2H2O → 2NaOH + H2
  • E 2Fe + 3CI2 → 2FeCI3
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Question 172:
Which of the following is not a direct petroleum product?
  • A Methane
  • B Ethanol
  • C Petrol
  • D Vaseline
  • E Kerosene
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Question 173:
How many principal electronic shells has an atom whose electronic configuration is shown below? 1s22s22p63s1
  • A 1
  • B 2
  • C 3
  • D 4
  • E 11
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Question 174:
Which of the following properties is not characteristic of electrovalent compounds?
  • A Formation of crystalline solids
  • B Solubility in polar solvents
  • C High vapour pressures
  • D High melting and boiling points
  • E Ability to conduct electricity in aqueous solution
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Question 175:
Compounds that have the same molecular formula but different structures are said to be
  • A Allotropic
  • B Polymorphic
  • C Polymeric
  • D Isomeric
  • E Isotopic
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