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    Rate Law mechanism observed

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    The rate law for the Br—- catalyzed reaction
    Br-
    C6H5NH2 + HNO2 + H+ C6H5N2+ + 2H2O

    is observed to be rate = = k [H+][HNO2][Br -].

    A proposed mechanism is
    k1
    (1) H+ + HNO2 H2NO2+ (rapid equilibrium)
    k-1

    k2
    (2) H2NO2+ + Br- NOBr + H2O (slow)

    k3
    (3) NOBr + C6H5NH2 C6H5N2+ + H2O + Br- (fast)

    Deduce the rate law for this mechanism and relate the observed rate constant k to the rate constants appearing in the assumed mechanism.

    Notes:
    1. Step (1) is a rapid equilibrium, meaning k1 and k-1 are much faster than k2.
    2. The forward and reverse rates are equal for step (1) since it is an equilibrium; this fact can
    be used to get an expression for the concentration of the intermediate H2NO2+.
    3. Recall, the reaction orders for elementary reactions are determined by the reaction
    stoichiometry.
    4. Step (2) is sufficiently slow that it can be considered rate-determining.

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    https://brainmass.com/chemistry/physical-chemistry/rate-law-mechanism-observed-286701

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    The rate law for the Br—- catalyzed reaction
    Br-
    C6H5NH2 + HNO2 + H+ C6H5N2+ + 2H2O

    is observed to be rate = = k [H+][HNO2][Br -].

    A proposed mechanism is
    k1
    (1) H+ + HNO2 H2NO2+ (rapid equilibrium)
    k-1

    k2
    (2) H2NO2+ + Br- NOBr + H2O (slow)

    k3
    (3) NOBr + C6H5NH2 C6H5N2+ + H2O + Br- (fast)

    Deduce the rate law for this mechanism and relate the observed rate ...

    Solution Summary

    The expert deduces the rate law for the mechanism that relates to the rate constant.

    $2.19

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