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 1251: Alkanals can be differentiated from alkanones by reaction with? Options:
  A) 2,4-dinitrophenylhydrazine
  B) hydrogen cyanide
  C) sodium hydrogen sulphite
  D) Tollen's reagent
  Show Answer
  The correct answer is D .
• Question 1252: The reaction of halogens in the presence of sunlight is an example of Options:
  A) oxidation reaction
  B) addition reaction
  C) hydrogenation reaction
  D) substitution reaction
  Show Answer
  The correct answer is D .
• Question 1253:

  SO${}_2$ + O${}_2$ 2SO${}_3$

  In the reaction above, the most suitable catalyst is?

  Options:
  A) chromium(vi)oxide
  B) iron(iii)oxide
  C) copper(i)oxide
  D) vanadium(v)oxide
  Show Answer
  The correct answer is D .
• Question 1254: Which of the following silver halides is readily soluble in ammonium hydroxide? Options:
  A) Agl
  B) AgBr
  C) AgCl
  D) AgF
  E) None of the above
  Show Answer
  The correct answer is C .
• Question 1255:

  

  2HCI_(ag) + CaCO_{3(s) → CaCl2(s)} + CO _2(g) +H₂O₍₁₎

  From the reaction above, which of the curves in the diagram represents the production of carbon (IV) oxide as dilute HCI is added?

  Options:
  A) L
  B) M
  C) N
  D) P
  Show Answer
  The correct answer is B .
• Question 1256: Which of the following statements is true of sulphur (IV) oxide? Options:
  A) It forms tetraoxosulphate (VI) acid with water
  B) It is an odourless gas
  C) It is an acid hybride
  D) It forms white precipitate with acidified barium chloride
  Show Answer
  The correct answer is C .
• Question 1257:

  3Cu + pHNO₃ →3Cu(NO)₂ + 4H₂ O + xNO

  In the equation above, the values of p and x respectively are

  Options:
  A) 1 and 3
  B) 2 and 3
  C) 6 and 2
  D) 8 and 2
  Show Answer
  The correct answer is D .
• Question 1258: The pH of a solution obtained by mixing 100cm³ of a 0.2M solution of NaOH is? Options:
  A) 1.3
  B) 7.0
  C) 9.7
  D) 12.7
  Show Answer
  The correct answer is D .
• Question 1259: The boiling point of water, ethanol, toluene and butan-2-ol are 373.0k, 351.3k, 383.6k and 372.5k respectively. Which liquid has the highest vapour pressure at 323.0k? Options:
  A) water
  B) toluene
  C) ethanol
  D) butan-2-ol
  E) none
  Show Answer
  The correct answer is C .
• Question 1260:

  

  Use the diagram to answer this question.

  The colour of the fountain water is

  Options:
  A) blue
  B) orange
  C) red
  D) yellow
  Show Answer
  The correct answer is C .