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 1291: Hydrogen diffuses through a porous plug Options:
  A) at the same rate as oxygen
  B) at a slower rate than oxygen
  C) twice as fast as oxygen
  D) three times as fast as oxygen
  E) four times as fast as oxygen
  Show Answer
  The correct answer is E .
• Question 1292: Which of the following represents ethyl ethanonate? Options:
  A) CH₃CH₂CO₂CH₃
  B) (CH₃CO₂)₂O
  C) CH₃CH₂CO₂CH₂CH₃
  D) CH₃CO₂CH₂CH₃
  E) CH₃CH₂COCH₂CH₃
  Show Answer
  The correct answer is D .
• Question 1293: 2SO_2(g) + O_2(g) 2SO₃. In the reaction above, the standard heats of formation of SO_2(g) and SO_3(g) are -297 KJ mol^-1 respectively. The heat change of the reaction is? Options:
  A) -99 kJ mol^-
  B) -198 kJ mol^-
  C) +198 kJ mol^-
  D) +683kJ mol^-
  Show Answer
  The correct answer is B .
• Question 1294: Which of the following types of bonding does not involve the formation of new substances? Options:
  A) Metallic
  B) covalent
  C) co-ordinate
  D) electrovalent
  Show Answer
  The correct answer is A .
• Question 1295:

  In the laboratory preparation of oxygen, the gas cannot be collected by displacement of air because

  Options:
  A) the density of oxygen is greater than that of air
  B) the density of air is nearly the same as that of oxygen
  C) oxygen is a component of air
  D) air is an impure substance
  Show Answer
  The correct answer is A .
• Question 1296:

  The cost of discharging 6.0g of a divalent metal, X from its salt is ₦12.00. What is the cost of discharging 9.0g of a trivalent metal, Y from its salt under the same condition?

  [X = 63, Y = 27, 1F = 96,500C]

  Options:
  A) N12.00
  B) N27.00
  C) N63.00
  D) N95.00
  Show Answer
  The correct answer is C .
• Question 1297:

  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 1298: Ethanol reacts with concentrated tetraoxosulphate (V) acid at a temperature above 170 ^oC to form Options:
  A) ethanone
  B) ethene
  C) ethyne
  D) ethanal
  Show Answer
  The correct answer is B .
• Question 1299: Which of the following compounds is NOT an isomers of 2,2 dimethylbutane? Options:
  A) 2-methylbutane
  B) 3-methylpentane
  C) 2,3-dimethylbutane
  D) 2-methylpentane
  Show Answer
  The correct answer is A .
• Question 1300:

  What volume of 0.100M sodium trioxonitrate (V) solution contains 5g of solute.

  [Na = 23, N = 14, O = 16]

  Options:
  A) 1.7 litres
  B) 0.420 litres
  C) 0.588 litres
  D) 2.35 litres
  Show Answer
  The correct answer is C .