Question #7b731

1 Answer
Apr 25, 2017

"1170 s"1170 s

Explanation:

All you have to do here is to use the integrated rate law for a second-order reaction that takes the form

"XY + XY " -> " products"XY + XY products

which will look like this

1/(["XY"]_ t) - 1/(["XY"]_ 0) = kt1[XY]t1[XY]0=kt

Here

  • ["XY"]_ 0[XY]0 is the initial concentration of the reactant
  • ["XY"]_ t[XY]t is the concentration of the reactant after a period of time tt
  • kk is the rate constant

In your case, you have

K = 6.82 * 10^(-3)K=6.82103 "M"^(-1)"s"^(-1)M1s1

and

{(["XY"]_ 0 = "0.140 M"), (["XY"]_ t = 6.60 * 10^(-2)"M") :}

Rearrange the integrated rate law to solve for t

t = (1/(["XY"]_ t) - 1/(["XY"]_ 0))/k

Plug in your values to find

t = ( 1/(6.60 * 10^(-2)color(red)(cancel(color(black)("M")))) - 1/(0.140color(red)(cancel(color(black)("M")))))/(6.82 * 10^(-3)color(red)(cancel(color(black)("M"^(-1))))"s"^(-1)) = color(darkgreen)(ul(color(black)("1170 s")))

The answer is rounded to three sig figs

If you want, you can convert this to minutes or to hours by using

"1 hour = 60 minutes = 3600 seconds"