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 1571: The major and most effective way of controlling pollution is to Options:
  A) improve machinery so that the substances released from combustion are less harmful
  B) pass strict laws against it by individuals and companies
  C) educate people on the causes and effects of pollution
  D) convert chemical wastes to harmless substances before releasing them into the environment
  Show Answer
  The correct answer is C .
• Question 1572: An example of a polysaccharides is? Options:
  A) —dextrose
  B) mannose
  C) glucose
  D) starch
  Show Answer
  The correct answer is D .
• Question 1573:

  The reactivity of fluorine is due to?

  Options:
  A) its high electro negativity
  B) small size of fluorine atom
  C) availability of D-orbitals
  D) strong f-f bond
  Show Answer
  The correct answer is A .
• Question 1574: Which of the following substances would you see as an indicator in the titration of sodium carbonate solution against hydrochloric acid (complete neutralisation)? Options:
  A) Litmus paper
  B) Phenolphthalein
  C) Methyl orange
  D) Universal indicator
  E) None of these
  Show Answer
  The correct answer is C .
• Question 1575:

  Which of the following pollutants will lead to the depletion of ozone layer?

  Options:
  A) chlorofluorocarbon
  B) carbon (ii) oxide
  C) hydrogen sulphide
  D) sulphur (iv) oxide
  Show Answer
  The correct answer is A .
• Question 1576: Which of the following is a solvent for perfumes? Options:
  A) C₅H₁₂
  B) C₄H₆
  C) CH₃COOH
  D) C₂H₅OH
  Show Answer
  The correct answer is D .
• Question 1577: When calcium oxide is heated with carbon, the oxide will Options:
  A) be converted to carbide
  B) be converted to the trioxocarbonate (IV) salt
  C) decompose to the metal
  D) melt,producingg carbon (IV) oxide
  Show Answer
  The correct answer is A .
• Question 1578:

  

  In the shown experiment (Fig. 1) the litmus paper will initially

  Options:
  A) be bleached
  B) turn green
  C) turn red
  D) turn blue
  Show Answer
  The correct answer is D .
• Question 1579: A solid begins to melt when? Options:
  A) constituent particles acquires a greater kinetic energy
  B) energy of vibration of particles of the solid is less than the intermolecular forces
  C) constituent particles acquires energy above the average kinetic energy
  D) energy of vibration of particles of the solid equals the intermolecular forces
  Show Answer
  The correct answer is A .
• Question 1580: How many unpaired electron(s) are there in the nitrogen sub-levels/ Options:
  A) 3
  B) 2
  C) 1
  D) none
  Show Answer
  The correct answer is A .