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 1801: The difference between colloides and and suspensions is brought out clearly by the fact that while colloids? Options:
  A) do not scatter light, suspensions do
  B) can be separated by filtration, suspension cannot be so separated
  C) can be separated by a membrane, suspensions cannot
  D) do not settle out on standing, suspensions do
  Show Answer
  The correct answer is D .
• Question 1802:

  Which of the following conditions will most enhance the spontaneity of a reaction?

  Options:
  A) $\mathrm{\Delta }$H is negative and greater than T$\mathrm{\Delta }$S
  B) $\mathrm{\Delta }$H is negative and $\mathrm{\Delta }$S = 0
  C) $\mathrm{\Delta }$H is positive and less than T$\mathrm{\Delta }$S
  D) $\mathrm{\Delta }$H is positive and equal to T$\mathrm{\Delta }$S
  Show Answer
  The correct answer is A .
• Question 1803: If an element X of an atomic number Z and mass number Y is irradiated by an intense concentration of neutrons, the relevant nuclear equation is? Options:
  A) ^y_zX + ¹₀n → ^{y - 1}_{z + 1}X
  B) ^y_zX + ¹₀n → ^{y + 1}_zX
  C) ^y_zX + ¹₀n → ^y_{z + 1}X
  D) ^y_zX + ¹₀n → ^{y + 1}_{z - 1}X
  Show Answer
  The correct answer is B .
• Question 1804: Which of the following alloys contain iron? Options:
  A) Duralumin and steel
  B) Brass and bronze
  C) Steel and permalloy
  D) Soft solder and duralumin
  Show Answer
  The correct answer is C .
• Question 1805: What is the volume of oxygen required to burn complete 45 cm³ of methane at s.t.p? Options:
  A) 135.0 cm³
  B) 180.0 cm³
  C) 45.0 cm³
  D) 90.0 cm³
  Show Answer
  The correct answer is D .
• Question 1806:

  

  In the diagram, the function of the concentrated H₂SO₄ is to

  Options:
  A) purify the gas
  B) dry the gas
  C) liquefty the gas
  D) remove odour
  Show Answer
  The correct answer is B .
• Question 1807: An increase in temperature causes an increase in pressure of a gas in a fixed volume due to an increase in the? Options:
  A) number of molecules of the gas
  B) density of the gas molecules
  C) number of collisions between the gas molecules
  D) number of collisions between the gas molecules and the walls of the container
  Show Answer
  The correct answer is D .
• Question 1808: Which of the following can be obtained by fractional distillation? Options:
  A) Nitrogen from liquid air
  B) Sodium chloride from sea water
  C) Iodine from a solution of Iondine in carbon tetrachloride
  D) Sulphur from a solution of sulphur incarbon disulphide
  Show Answer
  The correct answer is A .
• Question 1809:

  Which of the following is a common laboratory indicator for bases?

  Options:
  A) Methyl orange
  B) Phenolphthalein
  C) Bromothymol blue
  D) Litmus
  Show Answer
  The correct answer is B .
• Question 1810: The gas that is used for the treatment of cancer is Options:
  A) Neon
  B) Radon
  C) Xenon
  D) Argon
  Show Answer
  The correct answer is B .