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Thursday, 11 June 2026
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Chemistry Past Questions and Answers

Waec Chemistry Questions

Question 271:
When the trioxonitrate (IV) salt of an alkali metal Y is heated, the formula of the residue is
  • A Y2O
  • B YNO2
  • C Y2O3
  • D Y (NO2)2
  • E YO2
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Question 272:
Which of the following compounds of tin is a strong reducing agent?
  • A SnCI2
  • B SnCI4
  • C SnO2
  • D SnH4
  • E Sn(OH)2
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Question 273:
In which of the following pairs are both substances deliquescent?
  • A CaCI2 and H2SO4
  • B NaOH and MgSO4 7H2O
  • C CaCI2 and NaOH
  • D CUO and NaCI
  • E CaCO3 and MgCI2
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Question 274:
Producer gas is a mixture of
  • A Oxygen and hydrogen
  • B Hydrogen and nitrogen
  • C Nitrogen and oxygen
  • D Nitrogen and carbon (ll) oxide
  • E Hydrogen and carbon (ll) oxide
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Question 275:
An alkene may be converted to an alkane by
  • A Halogenation
  • B Hydrolysis
  • C Dehydration
  • D Hydrogenation
  • E Decomposition
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