B2027 Chem 2 Review (Sess. 2)

The following initial rate data for the reaction A + B --> C were obtained. Suppose the rate law can be written as:

rate = k[A]^x[B]^y

What is the value of x² + y²?

(a)  

The following rate data describes the reaction:

H₂O₂ + HI --> H₂O + I₂ (unbalanced)

What is the value of the rate constant for the reaction? Express your answer in 1 s.f. and decimal form (no units needed).

(a)  

Consider the reaction:

H₃AsO₄ + 2 H₃O⁺ + 3 I^- --> HAsO₂ + 4 H₂O + I₃

Choose the rate law of the reaction using the data shown.

• rate = k

  [H₃AsO₄][H₃O⁺][I^-]

• rate = k

  [H₃AsO₄][H₃O⁺]²[I^-]

• rate = k

  [H₃AsO₄]²[H₃O⁺][I^-]

• rate = k

  [H₃AsO₄][H₃O⁺][I^-]²

• rate = k

  [H₃AsO₄][H₃O⁺]²[I^-]²

Consider the reaction:

H₃AsO₄ + 2 H₃O⁺ + 3 I^- --> HAsO₂ + 4 H₂O + I₃

If the rate constant can be expressed as a x 10^b, find a + b (write in decimal form and don't round off).

(a)  

The reaction between hydrogen and nitrogen monoxide to form nitrogen gas and water was experimentally observed to have the rate law: rate = k[H₂][NO]².

Which of the following mechanisms DO NOT explain the observed rate law?

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The rate constant for a second-order reaction is 0.15 M^-1s^-1.  If the initial concentration of the reactant is 0.30 M, how long does it take (in seconds) for the concentration to decrease to 0.15 M?

(Report number only and 3 s.f.)

(a)  

What is the rate order of the reaction given the graphs in the figure.

• Zeroth Order

• First Order

• Second Order

• Third Order

Cyclopentane is unstable and decomposes by a first order reaction.  The rate constant for this reaction is 9.5 s^-1.  What is the half life of the reaction?

(Give numerical answer only to 3 s.f. and in decimal notation)

(a)  

Consider the time-evolution data of the reaction of 2 X --> Y + Z. What is the order of the reaction with respect to X?

• 0th Order

• 1st Order

• 2nd Order

• 3rd Order

• 4th Order

Fluorine-18 is a radioactive isotope that decays by positron emission to form oxygen-18 with a half-life of 109.7 min. (A positron is a particle with the mass of an electron and a single unit of positive charge). the equation is ¹⁸F₉ --> ¹⁸O₈ + ⁰e₁. Physicians use ¹⁸F to study the brain by injecting a quantity of fluoro-substituted glucose into the blood of a patient. The glucose accumulates in the regions where the brain is active and needs nourishment.

If a sample of glucose containing radioactive fluorine-18 is injected into the blood, what percent of the initial ¹⁸F isotope will remain after 5.59 h?

(Answer to 3 s.f. and with the % symbol: 1.01%)

(a)