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 191: The product formed when propanol is heated over a copper catalyst in the absence of oxygen are Options:
  A) CH₃CH₂CHO and H₂
  B) CH₃CHO and CO₂
  C) CH₃CH₂COOH and H₂
  D) CH₃COOH and CO₂
  Show Answer
  The correct answer is D .
• Question 192:

  

  Which of the five atoms can be described by the following properties: Relative atomic mass is greater than 30 but less than 40, it has odd atomic number and forms a unipositive ion in solution?

  Options:
  A) T
  B) W
  C) X
  D) Y
  E) Z
  Show Answer
  The correct answer is D .
• Question 193:

  The number of grammes of potassium hydroxide in 250cm³ of one molar solution is?

  (K = 39, O = 16, H = 1)

  Options:
  A) 40g
  B) 52g
  C) 100g
  D) 26g
  E) 14g
  Show Answer
  The correct answer is E .
• Question 194:

  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 195:

  When water drops are added to calcium carbide in a container and the gas produced is passed through a jet and lighted, the resultant flame is called an?

  Options:
  A) Oxyethene
  B) Oxyhydrocarbon flame
  C) Oxyacetylene flame
  D) Oxymethane flame
  Show Answer
  The correct answer is C .
• Question 196:

  Using the metal activity series, the metal that can liberate hydrogen gas from steam is?

  Options:
  A) iron
  B) copper
  C) tin
  D) lead
  Show Answer
  The correct answer is A .
• Question 197:

  What is the trend for ionization energy across a period in the periodic table?

  Options:
  A) Increases from left to right.
  B) Remains constant
  C) Varies randomly
  D) Decreases from left to right
  Show Answer
  The correct answer is A .
• Question 198:

  

  From the diagram above the mass of crystals deposited when 1 dm ³ of a saturated solution of NaCl is cooled from 80^oC to 60^oC is

  [Na = 23, Cl = 35.5]

  Options:
  A) 117.00 g
  B) 58.50 g
  C) 11.70 g
  D) 5.85 g
  Show Answer
  The correct answer is A .
• Question 199:

  I. H = 1s¹ II. N = 1s² 2s² p³ III. O = 1s² 2s² p⁴ IV. Zn = 1s² 2s² 2p⁶ 3s² 3p⁶ 4s² 3d¹⁰

  From the above, which of the following pairs is like to be paramagnetic?

  Options:
  A) I and II
  B) I and III
  C) I and IV
  D) III and IV
  Show Answer
  The correct answer is A .
• Question 200:

  

  The functional groups present in the compound above are

  Options:
  A) Alkene and halo-group
  B) Hydroxyl and chloro-group
  C) Alkene and chloro-group
  D) Hydroxyl and halo-group
  Show Answer
  The correct answer is B .