Chemistry Exam Past Questions and Answers | JAMB, WAEC and NECO

Chemistry is the study of the substances that make up matter. It looks at their properties, how they react with each other, and how these reactions can create new substances.

• Question 421: The molecular lattice of iodine is held together by Options:
  A) dative bond
  B) metallic bond
  C) hydrogen bond
  D) van der Waal's forces
  Show Answer
  The correct answer is D .
• Question 422: A burning candle produces water and Options:
  A) Carbon (II) oxide
  B) Carbon (IV) oxide
  C) Oxygen
  D) Hydrogen
  Show Answer
  The correct answer is B .
• Question 423: A particle that contains a protons, 10 neutrons and 10 electrons is Options:
  A) positive ion
  B) neutral atom of a metal
  C) neutral atom of a non-metal
  D) negative ion
  Show Answer
  The correct answer is D .
• Question 424:

  How many electrons will be found in the nucleus of an atom with mass number 23 and 17 neutrons?

  Options:
  A) none
  B) 6
  C) 7
  D) 8
  Show Answer
  The correct answer is A .
• Question 425:

  

  In the diagram above which of the cures illustrates Arrhenius' law?

  Options:
  A) Y
  B) Z
  C) R
  D) X
  Show Answer
  The correct answer is D .
• Question 426:

  Atoms of element X (with 2 electrons in the outer shell). combine with atoms of Y (with 7 electrons in the outer shell).

  Which of the following statements is FALSE? The compound formed

  Options:
  A) has formula XY
  B) is likely to be ionic
  C) contains X²⁺ ions
  D) contains Y^- ions
  Show Answer
  The correct answer is A .
• Question 427: The function of zinc electrode in a galvanic cells is that it Options:
  A) undergoes reduction
  B) serves as the positive electrode
  C) production electons
  D) uses up electrons
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  The correct answer is C .
• Question 428: Fluorine does not occur in the free state in nature because Options:
  A) it is a poisonous gas
  B) it belongs to the halogen family
  C) it is inert
  D) of its high reactivity
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  The correct answer is D .
• Question 429:

  A small quantity of solid ammonium chloride (NH₄Cl) was heated gently in a test tube, the solid gradually disappears to produce two gases. Later, a white cloudy deposit was observed on the cooler part of the test tube. The ammonium chloride is said to have undergone

  Options:
  A) distillation
  B) sublimation
  C) precipitation
  D) evaporation
  E) decomposition
  Show Answer
  The correct answer is B .
• Question 430: Alloys are best prepared by? Options:
  A) high temperature weilding of the metals
  B) electrolysis using the major metallic component as cathode
  C) reducing a mixture of the oxies of the elements
  D) cooling a molten mixture of the necessary elements
  Show Answer
  The correct answer is D .