Question

Consider this initial-rate data at a certain temperature for the reaction described by:

2NOCl(g) yields 2NO(g) + Cl2(g)

NOCl                                Intl. Rate of Form. of Cl2

(M)

.600                                   1.46 x 10^-5

.750                                   2.28 x 10^-5

.900                                    3.28 x 10^-5

Determine the value and units of the rate constant.

k=

Answer 1

-d[NOCl]/2dt= d/dt[Cl2]

NOCl             Initial rate of NOCl

0.6                      1.46*10-5/2 =0.73*10-5

0.75                  2.28*10-5/2= 1.14*10-5

0.9                     3.28*10-5/2= 1.64*10-5

the plot of -d[NOCl/dt Vs [NOCl] gave a straight line whose slope gives K. The reactin is second order.

The plot is shown below.

Rate constant = 2*10-5/M.time units ( since the rate units are not specified)