chemistry

posted by .

The first-order rate constant for photodissociation of A is 5.97 1/h. Calculate the time needed for the concentration of A to decrease to the following quantities.

a. 5% of its original value h

b. one-third of its initial concentration h

  • chemistry -

    k = 5.97 WHAT.
    ln(No/N) = kt
    ln(100/5) = 5.97*t
    Solve for t.
    I don't know the units (seconds, min, hours, days, years) because I can't tell from your value of 5.97 1/h.

  • chemistry -

    5.97 1/hour

  • chemistry -

    Then the time is in hours.
    b is worked the same way.

  • chemistry -

    could yo explain part b?

  • chemistry -

    Same equation.
    You can make up any number you want for No, then N is 1/3 that. I would pick a convenient number for No such as 300, then N = 100, and solve for t.
    No could be 1 and N = 1/3 etc.

  • chemistry -

    Thank You Very !

Respond to this Question

First Name
School Subject
Your Answer

Similar Questions

  1. Chemistry

    I know how to find half-lives, but I have trouble finding the length of time it would take for the concrentration of X to decrease to Y% of its initial value. For example, this is one of the problems: Methyl isocyanide, CH3NC, isomerizes …
  2. chemistry

    Butadiene, C4H6, in the gas phase undergoes a reaction to produce C8H12. The following data were obtained for the reaction. [C4H6] Time (min) 1 0 0.98 20 0.91 100 0.66 500 0.49 1000 0.32 2000 0.25 3000 Determine the order of the reaction. …
  3. Ap Chemistry

    I have no idea where to start with this problem: A certain reaction has the following general form: aA -> bB At a particular temperature and (A)o = 2.00(10^-2)M, concentration versus time data were collected for this reaction, and …
  4. AP Chemistry

    I have no idea where to start with this problem: A certain reaction has the following general form: aA -> bB At a particular temperature and (A)o = 2.00(10^-2)M, concentration versus time data were collected for this reaction, and …
  5. Chemistry

    The half-life for the second-order reaction of a substance A is 55.8 s when concentration of initial A = 0.69 M. Calculate the time needed for the concentration of A to decrease to the following values. (a) 1/8 of its original value …
  6. chemistry

    The reaction Cl(g)+ O3(g) --> ClO(g)+ O2(g) is the first-order in both reactants. Determine the pseudo-first-order and second-order rate constants for the reaction from the data in the table below if the initial ozone concentration …
  7. Chemistry

    What would be the concentration of dinitrogen pentoxide after 6.00 X 10(2) seconds and how long would it take for the concentration of N2O2 to decrease to 10.0% of its initial value in the following equation... N2O5 to NO2 and O2 initial …
  8. Chemistry

    The half-life for the second-order reaction of a substance A is 58.2 s when A0 = 0.63 mol L-1 Calculate the time needed for the concentration of A to decrease to the following values. (a) one-third of its original value (b) one-sixth …
  9. Science work

    A reaction is thought to be second order with respect to the concentration of carbon monoxide. What evidence would support this?
  10. Chemistry Lab

    *The decomposition of acetaldehyde is a first order reaction with a specific rate constant of 6.0 X 10^-1 / min. CH₃CHO --> CH₄ + CO 1. Calculate the initial rate when the concentration of acetaldehyde is 0.80M. 2. Calculate …

More Similar Questions