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Saturday, 13 June 2026
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Chemistry Past Questions and Answers

Waec Chemistry Questions

Question 376:
What name is given to each of the following? The
(a) irregular random movement of smoke particles in air.
(b) existence of an element in various forms in the same physical-state
(c) disintegration of atomic nuclei, accompanied with radiation emission.
(d) conversion of a solid difitrunto vapour without melting.
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    Question 377:
    (a)(i) Explain the term pH
    (ii) If sodium hydroxide solution were added to a solution of a strong acid, what would happen to the pH of the solution?

    (b) Give one example of each of the following:
    (i) acidic oxide
    (ii) acid salt.
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      Question 378:
      (a)(i) Sketch a graph to illustrate Charles' law.
      (ii) A gas occupies 500 cm\(^{ 3}\) at 2TC. calculate its volume at 40°C constant pressure.

      (b) List two gases that are used as refrigerant
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        Question 379:
        (a) State the type of reaction involved in the conversion of:
        (i) proteins.to amino acids:
        (ii) ethanol to ethene;
        (iii) benzene to bromobenzene

        (b) Write an equation to show that ethene reasts with hydrogen in the presence of finely divided nickel.
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          Question 380:
          (a) Name the device used for producing an electric current from a chemical
          (b) Copy and complete the table below.
          Electrolyte Product at the anode (carbon) Product at the cathode (carbon)
          Dilute NaCl\(_{(aq)}\)Concentrated NaCI\(_{(aq)}\)




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