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 1491: In the Haber process for the manufacture of ammonia, the catalyst commonly used is finely divided ? Options:
  A) vanadium
  B) platinum
  C) iron
  D) copper
  Show Answer
  The correct answer is C .
• Question 1492: A characteristic reaction of the compounds with the general formula C_nH_2n is Options:
  A) Esterification
  B) Polymerization
  C) Decarboxylation
  D) Substitution
  Show Answer
  The correct answer is B .
• Question 1493:

  What is the concentration of a solution containing 2g of NaOH in 100cm³ of solution?
  [Na = 23, O = 16, H = 1]

  Options:
  A) 0.40 mol dm^-3
  B) 0.50 mol dm^-3
  C) 0.05 mol dm^-3
  D) 0.30 mol dm^-3
  Show Answer
  The correct answer is B .
• Question 1494:

  In the reaction:

  M + N → P

  ΔH = +Q kJWhich of the following would increase the concentration of the product?

  Options:
  A) Adding a suitable catalyst
  B) Increasing the concentration of P
  C) Increasing the temperature
  D) Decreasing the temperature
  Show Answer
  The correct answer is C .
• Question 1495: 0.07g of a hydride of carbon occupies 56.0cm³ at S.T.P. when vaporized and contains 14.29% by mass of hydrocarbon is(C = 12, H = 1) Options:
  A) CH₄
  B) C₂H₂
  C) C₂H₄
  D) C₂H₆
  E) C₃H₈
  Show Answer
  The correct answer is C .
• Question 1496:

  How many electrons will be found in the nucleus of an atom with mass number 23 and 17 neutrons?

  Options:
  A) none
  B) 6
  C) 7
  D) 8
  Show Answer
  The correct answer is A .
• Question 1497:

  MnO_4(aq) + 8H + 5Fe²⁺ $\to$ Mn²⁺_(aq) + 5Fe³⁺_(aq) + H₂O.

  The oxidation number of manganese in the above reaction changed from

  Options:
  A) +7 to +2
  B) +6 to +2
  C) +5 to +2
  D) +4 to +2
  Show Answer
  The correct answer is A .
• Question 1498: The pollution from petroleum spillage in rivers and lakes can best be dispersed by Options:
  A) Pouring detergents
  B) Passing of ships through the area
  C) Pouring organic solvents
  D) Evaporation
  Show Answer
  The correct answer is A .
• Question 1499: Which of the following decrease when a given mass of gas is compressed to half its initial volume? Options:
  A) Atomic radius of each
  B) Average intermolecular distance
  C) Frequency of collisions
  D) Number of molecules presents
  Show Answer
  The correct answer is B .
• Question 1500:

  

  It can be deduced that the rate of the reaction

  Options:
  A) for bath l is higher than path ll
  B) for path ll is higher than path l
  C) is the same for both paths at all temperatures
  D) depends on the values of both x and y at all pressures
  Show Answer
  The correct answer is B .