A reaction in which A —–> products was monitored as a function of time and the results are shown below.

Answer 1

Zero order integrated rate law is:
[A] = [A]₀ – k∙t
[A]₀ denotes initial concentration.

So if you plot [A] versus t you get a straight line with the slope -k.
The result should be something about:
k = 3.4×10⁻³Ms⁻¹

Alternatively you can make regression analysis.
Least square fit of a line of the form
y = k∙x
to a set of data pairs (x,y)
leads to
k = ∑(y∙x) / ∑( x² )
(∑ denotes summation over all data points)

For this problem
x = t
y = [A]₀ – [A]
k = 3.41×10⁻³Ms⁻¹

The rate of a zero order reaction is dependent from the concentration level. As long as some reactant is present it will react away at the same, constant rate.:
rate = -d[A]/dt = k = 3.41×10⁻³Ms⁻¹

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