JAMB Chemistry questions: Water

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

1. Question 1· Water· JAMB

   Which process exchanges the Ca²⁺ and Mg²⁺ ions in hard water for Na⁺ ions?

   • Apassing the water through a permutit (ion-exchange) column
   • Bboiling
   • Cfiltration
   • Ddistillation

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   Explanation and discussion

2. Question 2· Water· JAMB

   In water treatment, suspended particles are removed mainly by

   • Afluoridation
   • Bchlorination
   • Csedimentation and sand filtration
   • Dboiling

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   Explanation and discussion

3. Question 3· Water· JAMB

   Temporary hardness of water is removed by

   • Aadding alum
   • Badding chlorine
   • Cfiltration
   • Dboiling

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4. Question 4· Water· JAMB

   Temporary hardness of water is caused by dissolved:

   • Acalcium sulphate
   • Bcalcium hydrogentrioxocarbonate(IV)
   • Cmagnesium chloride
   • Dsodium chloride

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5. Question 5· Water· JAMB

   Ion-exchange resins soften water by

   • Aremoving all dissolved salts as gas
   • Bboiling the water
   • Cadding chlorine
   • Dreplacing calcium and magnesium ions with sodium ions

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6. Question 6· Water· JAMB

   Which substance removes both temporary and permanent hardness of water?

   • Asodium trioxocarbonate(IV) (washing soda)
   • Bboiling
   • Calum
   • Dchlorine

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7. Question 7· Water· JAMB

   Water is regarded as a compound because

   • Ait dissolves many substances
   • Bit is a liquid
   • Cit boils at 100 °C
   • Dhydrogen and oxygen are always combined in a fixed ratio by mass

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8. Question 8· Water· JAMB

   Washing soda crystals, Na₂CO₃·10H₂O, lose water of crystallisation when exposed to air. They are described as

   • Adeliquescent
   • Befflorescent
   • Chygroscopic
   • Danhydrous

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9. Question 9· Water· JAMB

   Pure water at normal atmospheric pressure boils at

   • A110 °C
   • B0 °C
   • C90 °C
   • D100 °C

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10. Question 10· Water· JAMB

    Find the percentage of water by mass in Na₂CO₃·10H₂O. [Na = 23, C = 12, O = 16, H = 1]

    • A10%
    • B37.1%
    • C62.9%
    • D18%

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11. Question 11· Water· JAMB

    A substance that absorbs moisture from the air and dissolves in it to form a solution is described as

    • Aanhydrous
    • Befflorescent
    • Chygroscopic
    • Ddeliquescent

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12. Question 12· Water· JAMB

    Water dissolves many ionic substances because its molecules are

    • Avery large
    • Bnon-polar
    • Cpolar
    • Dmetallic

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13. Question 13· Water· JAMB

    Which of the following is hygroscopic and is used as a drying agent?

    • Asand
    • Bsodium chloride
    • Cconcentrated tetraoxosulphate(VI) acid
    • Dcopper

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14. Question 14· Water· JAMB

    In the treatment of town water, alum is added to

    • Amake suspended particles coagulate and settle
    • Bkill germs
    • Csoften the water
    • Dadd minerals

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15. Question 15· Water· JAMB

    Hard water forms scum with soap because

    • Ait contains dissolved oxygen
    • Bit contains sodium ions
    • Cit is too acidic
    • Dcalcium and magnesium ions react with the soap

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16. Question 16· Water· JAMB

    Soap forms scum in hard water because of dissolved

    • Acalcium and magnesium ions
    • Bsodium ions
    • Cchloride ions
    • Dhydrogen ions

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17. Question 17· Water· JAMB

    Permanent hardness of water can be removed by

    • Aboiling
    • Badding washing soda
    • Cfiltration
    • Dadding chlorine

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18. Question 18· Water· JAMB

    Water is called a universal solvent because it

    • Ais cheap
    • Bdissolves every substance
    • Cdissolves a wide range of substances
    • Dboils at 100 °C

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19. Question 19· Water· JAMB

    Sodium reacts with cold water to produce

    • Asodium oxide and oxygen
    • Bsodium hydroxide and hydrogen
    • Csodium chloride and water
    • Dsodium and steam

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20. Question 20· Water· JAMB

    When calcium hydrogentrioxocarbonate(IV) solution is boiled, it forms

    • Acalcium chloride
    • Bcalcium oxide and hydrogen
    • Ccalcium hydroxide only
    • Dcalcium trioxocarbonate(IV), water and carbon(IV) oxide

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