JAMB and WAEC Chemistry questions

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

1. Question 241· Chemical equilibrium· JAMB

   For N₂O₄ ⇌ 2NO₂ (ΔH positive), raising the temperature

   • Astops the reaction
   • Bshifts it to the left
   • Chas no effect
   • Dshifts the equilibrium to the right

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2. Question 242· Chemical equilibrium· WAEC

   For N₂ + 3H₂ ⇌ 2NH₃ (ΔH negative), the yield of ammonia increases if

   • Atemperature is increased
   • Bpressure is increased
   • Cammonia is added
   • Da catalyst is removed

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3. Question 243· Chemical equilibrium· WAEC

   Adding a catalyst to a system at equilibrium

   • Amakes equilibrium reached faster without changing its position
   • Bincreases the yield of products
   • Cshifts the equilibrium to the right
   • Dshifts the equilibrium to the left

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4. Question 244· Chemical equilibrium· JAMB

   Le Chatelier's principle states that when a system at equilibrium is disturbed, the system

   • Aalways moves to the right
   • Bstops reacting
   • Cshifts so as to oppose the disturbance
   • Dalways moves to the left

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5. Question 245· Chemical equilibrium· JAMB

   The equilibrium constant for N₂O₄(g) ⇌ 2NO₂(g) is

   • AK = [NO₂]/[N₂O₄]
   • BK = [N₂O₄]/[NO₂]²
   • CK = 2[NO₂]/[N₂O₄]
   • DK = [NO₂]²/[N₂O₄]

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6. Question 246· Chemical equilibrium· WAEC

   For N₂(g) + 3H₂(g) ⇌ 2NH₃(g), increasing the pressure

   • Ahas no effect on the equilibrium
   • Bshifts the equilibrium to the left
   • Cshifts the equilibrium to the right
   • Dstops the reaction

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7. Question 247· Chemical equilibrium· JAMB

   For 2NO₂(g) ⇌ N₂O₄(g), increasing the pressure

   • Ashifts the equilibrium to the left
   • Bshifts the equilibrium to the right
   • Chas no effect
   • Ddecomposes N₂O₄

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8. Question 248· Chemical equilibrium· JAMB

   In the Haber process, ammonia is removed from the equilibrium mixture by

   • Aburning it
   • Bdissolving it in oil
   • Ccooling, so that it liquefies
   • Dpassing it over iron

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9. Question 249· Chemical equilibrium· JAMB

   The equilibrium constant Kc of a reaction changes only when the

   • Atemperature changes
   • Bpressure changes
   • Cconcentration changes
   • Da catalyst is added

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10. Question 250· Chemistry and industry· WAEC

    Nitrogen-containing fertilisers such as urea are produced in Nigeria using ammonia made by

    • Athe contact process
    • Bthe Haber process
    • Cthe Solvay process
    • Dfermentation

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11. Question 251· Chemistry and industry· JAMB

    Refinery gas from the distillation of crude oil is used mainly as

    • Acandle wax
    • Broad surfacing
    • Clubricant
    • Dfuel gas (LPG)

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12. Question 252· Chemistry and industry· WAEC

    The Haber process is used to manufacture

    • Aammonia
    • Bsulphuric acid
    • Cnitric acid
    • Dchlorine

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13. Question 253· Chemistry and industry· JAMB

    An advantage of soapless detergents over soap is that detergents

    • Aare made from animal fat
    • Bare always biodegradable
    • Clather well even in hard water
    • Dare cheaper to make from palm oil

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14. Question 254· Chemistry and industry· WAEC

    Fertiliser plants in Nigeria use natural gas mainly as a source of

    • Ahydrogen for ammonia production
    • Boxygen
    • Cnitrogen only
    • Dchlorine

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15. Question 255· Chemistry and industry· JAMB

    The hydrogenation of vegetable oils is used to produce

    • Asoap
    • Bmargarine
    • Cdetergents
    • Dpetrol

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16. Question 256· Chemistry and industry· JAMB

    In the Contact process, SO₃ is dissolved in concentrated tetraoxosulphate(VI) acid to form

    • Aoleum
    • Bdilute acid
    • Csulphur
    • Dsulphur(IV) oxide

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17. Question 257· Chemistry and industry· JAMB

    The raw materials for the Haber process are

    • Asulphur and oxygen
    • Bnitrogen from the air and hydrogen from natural gas
    • Csalt and limestone
    • Dcoal and iron

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18. Question 258· Chemistry and industry· WAEC

    Soap is made by boiling fats or oils with

    • Aethanol
    • Bsulphuric acid
    • Csodium hydroxide
    • Dsodium chloride

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19. Question 259· Chemistry and industry· WAEC

    The fraction of crude oil used as fuel for jet aircraft is

    • Abitumen
    • Bkerosene
    • Clubricating oil
    • Dpetroleum gas

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20. Question 260· Chemistry and industry· JAMB

    Ammonia is used mainly in the manufacture of

    • Aglass
    • Bfertilisers
    • Csteel
    • Dcement

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    Explanation and discussion