Waec Chemistry Past Questions For Year 1992

Question 6

If the volume of a given mass of gas at 298 K and pressure of 205.2 x 10\(^3\) Nm\(^{-2}\) is 2.12dm\(^3\), what is volume of the gas at s.t.p? (Standard pressure = 101.3 x 10\(^3\) Nm\(^{-2}\), Standard temperature = 273K)

waec 1992

  • A. 39.3dm 3
  • B. 22.4dm3
  • C. 4.93dm3
  • D. 3.93dm3
  • E. 0.393dm3
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Question 7

Which of the following processes is a physical reaction?

waec 1992

  • A. Electrolysis
  • B. Hydrolysis
  • C. Allotropic change
  • D. Neutralization
  • E. Corrosion
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Question 8

Study carefully the reaction represented by the equation below. 2H2O 2(l) → O 2(g) + 2H2O(l). Which of the following will not reaction increase the reaction rate?

waec 1992

  • A. Heating the hydrogen peroxide
  • B. Adding a pinch of MnO2 to the reactant
  • C. increasing the concentration of the H2O2
  • D. Adding water to the reactant
  • E. Exposing the reactant to sunlight
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Question 9

''The rate a reaction is proportional to the number of effective collisions occurring per second between the reactants''. This statement is associated with the

waec 1992

  • A. Kinetic theory
  • B. rate law
  • C. atomic theory
  • D. collision theory
  • E. gas laws
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Question 10

What is the quantity of electricity produced when a current of 0.5A is passed for 5 hours 45 mins? (1F = 96500C)

waec 1992

  • A. 0. 11F
  • B. 0.12F
  • C. 0.22F
  • D. 1.1F
  • E. 2.2F
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