WAEC Chemistry questions: Acids, bases and salts

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

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

   A solution with pH 9 is

   • Aweakly acidic
   • Bstrongly acidic
   • Cneutral
   • Dweakly alkaline

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2. Question 2· Acids, bases and salts· WAEC

   Baking soda used in cooking is

   • Asodium hydrogentrioxocarbonate(IV)
   • Bsodium chloride
   • Ccalcium oxide
   • Dammonium chloride

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

   Hydrated salts lose water of crystallisation on exposure to air. This is

   • Asublimation
   • Bdeliquescence
   • Chygroscopy
   • Defflorescence

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

   A salt formed when only part of the replaceable hydrogen of an acid is replaced by a metal is

   • Aa normal salt
   • Ban acid salt
   • Ca basic salt
   • Da double salt

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

   Which of these is a weak acid?

   • Aethanoic acid
   • Bhydrochloric acid
   • Ctrioxonitrate(V) acid
   • Dtetraoxosulphate(VI) acid

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6. Question 6· Acids, bases and salts· WAEC

   An acid salt is formed when

   • Athe replaceable hydrogen of an acid is only partly replaced
   • Ball hydrogen is replaced
   • Can acid reacts with water
   • Da base dissolves

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7. Question 7· Acids, bases and salts· WAEC

   25 cm³ of 0.1 mol/dm³ NaOH is neutralised by 20 cm³ of HCl. The concentration of the acid is

   • A0.1 mol/dm³
   • B0.08 mol/dm³
   • C0.125 mol/dm³
   • D0.25 mol/dm³

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

   The pH of a 0.01 mol/dm³ solution of HCl is

   • A0.01
   • B1
   • C12
   • D2

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9. Question 9· Acids, bases and salts· WAEC

   An aqueous solution of pH 12 is

   • Astrongly acidic
   • Bweakly acidic
   • Cneutral
   • Dstrongly alkaline

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10. Question 10· Acids, bases and salts· WAEC

    A solution of household bleach has a pH of 12. It is

    • Aneutral
    • Bstrongly acidic
    • Cstrongly alkaline
    • Dweakly acidic

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11. Question 11· Acids, bases and salts· WAEC

    According to Brønsted-Lowry, an acid is a

    • Ahydroxide donor
    • Bproton acceptor
    • Celectron donor
    • Dproton donor

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

    The reaction of an acid with a base to form a salt and water only is called

    • Aoxidation
    • Bhydrolysis
    • Cneutralisation
    • Desterification

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

    25.0 cm³ of 0.10 mol/dm³ sodium hydroxide is exactly neutralised by 20.0 cm³ of hydrochloric acid. Find the concentration of the acid.

    • A0.25 mol/dm³
    • B0.080 mol/dm³
    • C0.10 mol/dm³
    • D0.125 mol/dm³

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

    A farmer adds lime to his soil in order to

    • Areduce the acidity of the soil
    • Bincrease the acidity of the soil
    • Ckill weeds
    • Dadd nitrogen

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15. Question 15· Acids, bases and salts· WAEC

    The reaction between an acid and a base to form salt and water only is called

    • Aprecipitation
    • Bhydrolysis
    • Coxidation
    • Dneutralisation

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16. Question 16· Acids, bases and salts· WAEC

    A solution with a pH of 12 is

    • Astrongly acidic
    • Bstrongly alkaline
    • Cweakly acidic
    • Dneutral

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

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

    • A7
    • B1
    • C4
    • D3

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18. Question 18· 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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19. Question 19· Acids, bases and salts· WAEC

    Lemon juice tastes sour because it contains

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

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20. Question 20· 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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    Explanation and discussion