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Thursday, 21 May 2026
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Chemistry Past Questions and Answers

Chemistry Questions

Question 561:
The forces holding naphthalene crystals together can be overcome when naphthalene is heated to a temperature of 354K resulting in the crystal to melting. These forces are known as?
  • A Coulombic
  • B Ionic
  • C Covalent
  • D Van der waals
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Question 562:
A metallic ion X<sup style='font-size: smaller;'>2+</sup> with an inert gas structure contains 18 electrons. How many protons are there in this ion?
  • A 20
  • B 18
  • C 16
  • D 2
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Question 563:
Which of the following physical properties decreases across the Periodic Table?
  • A Ionization potenial
  • B Electron affinity
  • C Electronegativity
  • D Atomic radius
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Question 564:
What are the possible oxidation numbers of an element if its atomic number is 17?
  • A -1 and 7
  • B -1 and 6
  • C -3 and 5
  • D -2 and 6
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Question 565:
The energy changes accompanying the addition of an electron to a gaseous atom is called?
  • A First ionization energy
  • B Second ionization energy
  • C Electron affinity
  • D Electronegativity
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