JAMB Chemistry questions: Rates of chemical reaction

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

1. Question 1· Rates of chemical reaction· JAMB

   Sunlight speeds up the reaction between hydrogen and chlorine because it

   • Asupplies energy to break Cl–Cl bonds
   • Bcools the mixture
   • Cis a reactant
   • Dremoves the product

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2. Question 2· Rates of chemical reaction· JAMB

   Which of the following reactions is greatly speeded up by light?

   • Azinc and dilute acid
   • Bhydrogen and chlorine forming hydrogen chloride
   • Cneutralisation of an acid by an alkali
   • Ddecomposition of limestone

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3. Question 3· Rates of chemical reaction· JAMB

   The rate of a reaction is greatest at the start and falls with time because

   • Amore products slow the reaction
   • Bthe catalyst is used up
   • Cthe temperature always falls
   • Dthe concentration of the reactants decreases

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4. Question 4· Rates of chemical reaction· JAMB

   

   In the energy profile shown, the energy labelled X is the

   • Aactivation energy
   • Benthalpy change of the reaction
   • Cenergy of the products
   • Dbond energy of the products

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5. Question 5· Rates of chemical reaction· JAMB

   Photographic film works because silver halides

   • Abecome magnetic
   • Bmelt in light
   • Cdissolve in light
   • Ddecompose when exposed to light

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6. Question 6· Rates of chemical reaction· JAMB

   Increasing the concentration of an acid increases its rate of reaction with marble because

   • Athe marble becomes larger
   • Bthe activation energy rises
   • Cthe reacting particles collide more often
   • Dthe temperature falls

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7. Question 7· Rates of chemical reaction· JAMB

   Enzymes are

   • Ametals
   • Binorganic acids
   • Csimple sugars
   • Dbiological catalysts

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8. Question 8· Rates of chemical reaction· JAMB

   A suitable unit for the rate of reaction measured as change in concentration with time is

   • Amol dm⁻³ s⁻¹
   • Bmol dm⁻³
   • Cs⁻¹ only
   • DkJ mol⁻¹

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9. Question 9· Rates of chemical reaction· JAMB

   A substance that slows down a chemical reaction is called

   • Aa catalyst
   • Ban inhibitor
   • Ca reactant
   • Dan enzyme only

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10. Question 10· Rates of chemical reaction· JAMB

    A negative catalyst (inhibitor)

    • Achanges ΔH
    • Bspeeds up a reaction
    • Cslows down a reaction
    • Dstarts a reaction

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11. Question 11· Rates of chemical reaction· JAMB

    Increasing the concentration of reactants increases the rate because

    • Athe catalyst is used up
    • Bactivation energy falls
    • CΔH changes
    • Dcollisions become more frequent

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12. Question 12· Rates of chemical reaction· JAMB

    The rate of the reaction between magnesium and dilute hydrochloric acid can be followed by collecting the hydrogen in a

    • Apipette
    • Bburette
    • Cgas syringe
    • Dcrucible

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13. Question 13· Rates of chemical reaction· JAMB

    According to the collision theory, a reaction takes place when particles collide

    • Aonly when heated
    • Bat any speed
    • Conly in the solid state
    • Dwith enough energy and in the right orientation

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14. Question 14· Rates of chemical reaction· JAMB

    The rate of a reaction that gives off a gas can be followed by measuring the

    • Acolour of the container
    • Bvolume of gas produced per unit time
    • Cmass of the burner
    • Dsize of the beaker

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15. Question 15· Rates of chemical reaction· JAMB

    Powdered marble reacts faster with dilute acid than lumps of marble of the same mass because the powder has a

    • Ahigher temperature
    • Blarger surface area
    • Chigher concentration
    • Dlower activation energy

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16. Question 16· Rates of chemical reaction· JAMB

    An enzyme is

    • Aa product
    • Ban inhibitor
    • Ca reactant
    • Da biological catalyst

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17. Question 17· Rates of chemical reaction· JAMB

    When dilute hydrochloric acid reacts with marble chips, the gas collected to follow the rate is

    • Achlorine
    • Bhydrogen
    • Coxygen
    • Dcarbon(IV) oxide

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18. Question 18· Rates of chemical reaction· JAMB

    A catalyst increases the rate of a reaction by

    • Aincreasing the temperature
    • Blowering the activation energy
    • Cincreasing the concentration
    • Dshifting the equilibrium

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19. Question 19· Rates of chemical reaction· JAMB

    The decomposition of hydrogen peroxide into water and oxygen is catalysed by

    • Amanganese(IV) oxide
    • Bsodium chloride
    • Ccopper(II) oxide only when wet
    • Dsulphur

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20. Question 20· Rates of chemical reaction· JAMB

    A suitable unit for the rate of a reaction is

    • Adm³
    • Bmol
    • Cmol dm⁻³ s⁻¹
    • Ds

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    Explanation and discussion