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 361:

  Pure sulphuric acid is a liquid of 1:84 density. What volume of it would be required to prepare 250 cm³ of 2.0 M solution?

  (H = 1, S = 32, O = 16)

  Options:
  A) 2.00
  B) 2.66
  C) 3.00
  D) 3.66
  E) 4.00
  Show Answer
  The correct answer is B .
• Question 362: The relationship between the velocity (U) of gas molecules and their relative molecular mass (M) is shown by the equation Options:
  A) U = (kM)$\frac{1}{2}$
  B) U = (kM)²
  C) U = $\sqrt{k}m$
  D) U = ($\frac{k}{m}$)${}^{\frac{1}{2}}$
  Show Answer
  The correct answer is C .
• Question 363:

  Duralumin consists of aluminum, copper?

  Options:
  A) Zinc and Gold
  B) Lead and Manganese
  C) Nickel and Silver
  D) Manganese and Magnesium
  Show Answer
  The correct answer is D .
• Question 364:

  The only metal that is anti-bacterial is?

  Options:
  A) Iron
  B) Sodium
  C) Alluminium
  D) Copper
  Show Answer
  The correct answer is D .
• Question 365: In the reaction of oxygen with hydrogen to produce water, which of the following statements is true? Options:
  A) One atom of hydrogen reacts with two atoms of oxygen to give one molecule of water
  B) Two atoms of hydrogen react with two atoms of oxygen to give two molecules of water
  C) One molecule of oxygen reacts with one molecule of hydrogen to give two molecules of water
  D) One molecule of hydrogen reaccts with two molecules of oxygen to give three molecules of water
  E) One molecule of oxygen reacts with two molecules of hydrogen to give two molecules of water
  Show Answer
  The correct answer is E .
• Question 366:

  What is the chemical formula of rust, which is formed on the surface of iron in the presence of oxygen and moisture?

  Options:
  A) Fe${}_3$O${}_4$
  B) FeO
  C) Fe(OH)3
  D) Fe${}_2$O${}_3$
  Show Answer
  The correct answer is D .
• Question 367:

  How many grams of methylacetylene (propyne) CH₃ - C Ξ CH will completely discharge the colour of 8g of bromine?

  (Br = 80, C = 12, H = 1)

  Options:
  A) 0.5
  B) 1.0
  C) 2.0
  D) 3.0
  E) 4.0
  Show Answer
  The correct answer is B .
• Question 368: When sodium nitrate dissolves in water, ∆H is positive. This means that? Options:
  A) the reaction is catalysed
  B) the reaction is complete
  C) the reaction is exothermic
  D) the reaction is endthermic
  E) sodium nitrate is highly soluble in water
  Show Answer
  The correct answer is D .
• Question 369:

  A metal M displaces zinc from ZnCl, solution, solution

  This shows that

  Options:
  A) electrons flow from zinc to M
  B) M is more electropositive than zinc
  C) M is more electonegative than zinc
  D) zinc is more electropositive than M
  Show Answer
  The correct answer is B .
• Question 370:

  4g each of aluminium foil and aluminium powder were introduced respectively into flasks P and Q.

  Flask P was treated with warm bench sodium hydroxide and all the aluminium dissolved in one hour. Flask Q was treated with cold sodium hydroxide and all the aluminium dissolved in 10 minutes. What was responsible for Q reacting faster than P?

  Options:
  A) There were more aluminium atoms in Q than P
  B) The heat given off in retarded the reaction
  C) Q generated more pressure than P during the reaction
  D) P generated more pressure than Q
  E) Q has a greater surface area for the reaction than P
  Show Answer
  The correct answer is E .