JAMB and WAEC Chemistry questions

800 questions with answers and explanations. Tap an option to check yourself.

1. Question 41· Acids, bases and salts· WAEC

   What is the basicity of tetraoxophosphate(V) acid, H₃PO₄?

   • A7
   • B1
   • C4
   • D3

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2. Question 42· Acids, bases and salts· JAMB

   A strong acid is one that

   • Ais very concentrated
   • Bis completely ionised in water
   • Chas a pH of 7
   • Ddoes not conduct electricity

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3. Question 43· Acids, bases and salts· WAEC

   A suitable indicator for titrating a strong acid with a weak base is

   • Aphenolphthalein
   • Bmethyl orange
   • Clitmus paper only
   • Duniversal indicator

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4. Question 44· Acids, bases and salts· WAEC

   Lemon juice tastes sour because it contains

   • Aa salt
   • Ba base
   • Can acid
   • Dwater only

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5. Question 45· Acids, bases and salts· WAEC

   Which of these is a basic oxide?

   • Asulphur(IV) oxide
   • Bsodium oxide
   • Ccarbon(IV) oxide
   • Dnitrogen(IV) oxide

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6. Question 46· Acids, bases and salts· JAMB

   According to Arrhenius, a base is a substance that in water produces

   • Achloride ions
   • Bhydrogen ions
   • Chydroxide ions
   • Doxide ions

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7. Question 47· Acids, bases and salts· JAMB

   20 cm³ of 0.15 mol/dm³ H₂SO₄ exactly neutralises 30 cm³ of NaOH solution. Find the concentration of the NaOH.

   • A0.1 mol/dm³
   • B0.2 mol/dm³
   • C0.3 mol/dm³
   • D0.15 mol/dm³

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8. Question 48· Acids, bases and salts· WAEC

   Which indicator is most suitable for titrating a strong acid against a weak base?

   • Apotassium manganate(VII)
   • Bphenolphthalein
   • Cstarch
   • Dmethyl orange

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9. Question 49· Acids, bases and salts· JAMB

   How many moles of sodium hydroxide are needed to neutralise 20 cm³ of 0.1 mol/dm³ tetraoxosulphate(VI) acid?

   • A0.02 mol
   • B0.002 mol
   • C0.004 mol
   • D0.001 mol

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10. Question 50· Acids, bases and salts· JAMB

    An acid reacts with a trioxocarbonate(IV) to produce

    • Aan alkali only
    • Ba salt and hydrogen
    • Ca base and water
    • Da salt, water and carbon(IV) oxide

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11. Question 51· Acids, bases and salts· JAMB

    Find the pH of a 0.01 mol/dm³ solution of hydrochloric acid, assuming complete ionisation.

    • A1
    • B2
    • C0.01
    • D12

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12. Question 52· Acids, bases and salts· WAEC

    An acid turns blue litmus paper

    • Acolourless
    • Bgreen
    • Cyellow
    • Dred

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13. Question 53· Acids, bases and salts· WAEC

    Zinc granules react with dilute hydrochloric acid to give

    • Azinc oxide and chlorine
    • Bzinc chloride and hydrogen
    • Czinc chloride and water
    • Dzinc hydroxide and hydrogen

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14. Question 54· Acids, bases and salts· WAEC

    Which salt is insoluble in water?

    • Abarium sulphate
    • Bsodium chloride
    • Cpotassium nitrate
    • Dammonium chloride

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15. Question 55· Acids, bases and salts· JAMB

    Which of these is an amphoteric oxide?

    • Acalcium oxide
    • Bsodium oxide
    • Csulphur(VI) oxide
    • Daluminium oxide

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16. Question 56· Acids, bases and salts· JAMB

    The salt formed when zinc reacts with dilute tetraoxosulphate(VI) acid is

    • Azinc oxide
    • Bzinc chloride
    • Czinc trioxonitrate(V)
    • Dzinc tetraoxosulphate(VI)

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17. Question 57· Acids, bases and salts· WAEC

    Pure water at 25 °C has a pH of

    • A14
    • B0
    • C7
    • D1

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18. Question 58· Acids, bases and salts· WAEC

    What volume of 0.1 mol/dm³ NaOH will exactly neutralise 25 cm³ of 0.1 mol/dm³ HCl?

    • A2.5 cm³
    • B50 cm³
    • C12.5 cm³
    • D25 cm³

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19. Question 59· Air· WAEC

    The components of air can be separated by

    • Achromatography
    • Bfiltration
    • Celectrolysis
    • Dfractional distillation of liquid air

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20. Question 60· Air· WAEC

    Noble gases are used in electric bulbs because they are

    • Aflammable
    • Bcoloured
    • Cunreactive
    • Ddense

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    Explanation and discussion