WAEC Chemistry questions: Kinetic theory of matter and gas laws

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

1. Question 1· Kinetic theory of matter and gas laws· WAEC

   The change of a gas directly to a solid is called

   • Adeposition
   • Bsublimation
   • Cevaporation
   • Dmelting

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2. Question 2· Kinetic theory of matter and gas laws· WAEC

   A gas occupies 120 cm³ at 1 atm. What volume does it occupy at 3 atm at constant temperature?

   • A360 cm³
   • B40 cm³
   • C120 cm³
   • D20 cm³

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3. Question 3· Kinetic theory of matter and gas laws· WAEC

   A gas at 2 atm and 300 K is heated at constant volume to 450 K. Its new pressure is

   • A1.33 atm
   • B3 atm
   • C4.5 atm
   • D2 atm

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4. Question 4· Kinetic theory of matter and gas laws· WAEC

   The relative rates of diffusion of hydrogen and oxygen are

   • A2 : 1
   • B1 : 4
   • C16 : 1
   • D4 : 1

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5. Question 5· Kinetic theory of matter and gas laws· WAEC

   At s.t.p., one mole of any gas occupies a volume of

   • A24.0 dm³
   • B22.4 dm³
   • C1.0 dm³
   • D11.2 dm³

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6. Question 6· Kinetic theory of matter and gas laws· WAEC

   The particles of a solid

   • Amove freely in all directions
   • Bvibrate about fixed positions
   • Care far apart
   • Dhave no attraction for one another

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7. Question 7· Kinetic theory of matter and gas laws· WAEC

   Why does the pressure of gas in a sealed tin rise when the tin is heated?

   • AIts molecules become larger
   • BIts molecules move faster and hit the walls harder and more often
   • CThe number of molecules increases
   • DIts molecules attract each other more

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8. Question 8· Kinetic theory of matter and gas laws· WAEC

   Which gas diffuses fastest?

   • Achlorine
   • Boxygen
   • Chydrogen
   • Dcarbon dioxide

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9. Question 9· Kinetic theory of matter and gas laws· WAEC

   Which of the following gases diffuses fastest? (H = 1, He = 4, C = 12, O = 16)

   • AO₂
   • BH₂
   • CCO₂
   • DHe

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10. Question 10· Kinetic theory of matter and gas laws· WAEC

    Which assumption of the kinetic theory fails for real gases at high pressure?

    • Athat the volume of the molecules themselves is negligible
    • Bthat molecules move randomly
    • Cthat collisions occur
    • Dthat gases have mass

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11. Question 11· Kinetic theory of matter and gas laws· WAEC

    Which of these gases diffuses fastest at the same temperature? [H = 1, He = 4, N = 14, O = 16]

    • Aoxygen
    • Bammonia
    • Cnitrogen
    • Dhelium

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12. Question 12· Kinetic theory of matter and gas laws· WAEC

    A gas has a volume of 250 cm³ at 27 °C. Find its volume at 87 °C at constant pressure.

    • A250 cm³
    • B805 cm³
    • C208 cm³
    • D300 cm³

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13. Question 13· Kinetic theory of matter and gas laws· WAEC

    Diffusion is fastest in

    • Asolids
    • Bliquids
    • Cgases
    • Dmetals

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14. Question 14· Kinetic theory of matter and gas laws· WAEC

    Gas X diffuses four times as fast as oxygen under the same conditions. Find the relative molecular mass of X. [O = 16]

    • A16
    • B8
    • C128
    • D2

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15. Question 15· Kinetic theory of matter and gas laws· WAEC

    According to the kinetic theory, gas pressure is caused by

    • Aattraction between molecules
    • Bcollisions of molecules with the container walls
    • Cthe weight of the gas only
    • Dheat alone

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16. Question 16· Kinetic theory of matter and gas laws· WAEC

    According to the kinetic theory, the particles of a gas

    • Aare at rest
    • Bare fixed in position
    • Cattract each other strongly
    • Dmove randomly at high speed

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17. Question 17· Kinetic theory of matter and gas laws· WAEC

    A fixed mass of gas occupies 600 cm³ at 300 K and 1 atm. Find its volume at 400 K and 2 atm.

    • A900 cm³
    • B400 cm³
    • C225 cm³
    • D1600 cm³

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18. Question 18· Kinetic theory of matter and gas laws· WAEC

    The particles in a solid

    • Amove freely in all directions
    • Bvibrate about fixed positions
    • Care far apart
    • Dhave no forces between them

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    Explanation and discussion