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 1671:

  The following non-metal form acidic oxides with oxygen except?

  Options:
  A) phosphorus
  B) sulphur
  C) carbon
  D) chlorine
  Show Answer
  The correct answer is C .
• Question 1672:

  A dense white fume is formed when ammonia gas reacts with

  Options:
  A) O_2(g)
  B) H_2(g)
  C) Cl_2(g)
  D) HCl_(g)
  Show Answer
  The correct answer is D .
• Question 1673: Which of the following are produced when ammonium trioxonitrate (V) crystals are cautiously heated in a hard glass round bottomed flask? Options:
  A) N₂O and steam
  B) NO₂ and ammonia
  C) N₂O₂ and NO₂
  D) NO and NO₂
  Show Answer
  The correct answer is A .
• Question 1674: When sodium ethanoate is treated with a few drops of concentrated tetraoxosulphate(vi)acid. one of the products is Options:
  A) CH₃COOH
  B) CH₃COOCH₃
  C) CH₃COOC₂H₅
  D) C₂H₅COOCH₃
  Show Answer
  The correct answer is A .
• Question 1675: The number of atoms in one mole of a substance is equal to? Options:
  A) the atomic number
  B) the avogadro number
  C) the gas constant
  D) the number of neutrons
  E) the number of electrons
  Show Answer
  The correct answer is B .
• Question 1676: A jet plane carrying 3,000 kg of ethane burns off all the gas forming water and carbondioxide. if all the carbondioxide is expelled and all the water formed is condensed and kept on board the plane, then the gain in weight is Options:
  A) 1,800 kg
  B) 900 kg
  C) 600 kg
  D) 2, 400 kg
  E) 1, 200 kg
  Show Answer
  The correct answer is D .
• Question 1677: In order to remove one electron from a 3S orbital of gaseous sodium atom, about 496KJMol^-1 of energy is required. This energy is referred to as Options:
  A) electron affinity
  B) ionization energy
  C) activation evergy
  D) electronegativity
  Show Answer
  The correct answer is B .
• Question 1678: Which of the following properties is NOT peculiar to matter? Options:
  A) kinetic energy of particles increase from solid to gas
  B) Random motion of particles increases from liquid to gas
  C) Orderliness of particles increases from gas to liquid
  D) Random motion of particles increases from gas to solid
  Show Answer
  The correct answer is D .
• Question 1679: Which of the following statements is FALSE? Options:
  A) Copper (ll) ion can be reduced to copper (l) ion by hydrochloric acid and zinc
  B) Sodium metal dissolves in water giving oxygen
  C) Nitrogen is insoluble in water
  D) Carbondioxide is soluble in water
  E) lead has a higher atomic weight than copper
  Show Answer
  The correct answer is B .
• Question 1680: Water for town supply is chlorinate to make it free from Options:
  A) bad colour
  B) bacteria
  C) temporary hardness
  D) permanent hardness
  Show Answer
  The correct answer is B .