Question

The reactant concentration in a zero-order reaction was 6.00×10−2 M

after 175 s
and 3.50×10−2 M
after 315 s
. What is the rate constant for this reaction?

Answer 1

In a zero-order reaction, the rate of the reaction is independent of the concentration of the reactant. Therefore, the rate of the reaction is constant over time. We can use the following equation to determine the rate constant (k) for a zero-order reaction:

Rate = k

The units of k for a zero-order reaction are M/s.

To determine the rate constant for this reaction, we can use the two given concentrations and times:

Rate = (6.00×10^-2 M - 3.50×10^-2 M) / (315 s - 175 s)
Rate = 2.5×10^-3 M/s

Since the rate of a zero-order reaction is constant, we can set the rate equal to the rate constant:

k = Rate = 2.5×10^-3 M/s

Therefore, the rate constant for this zero-order reaction is 2.5×10^-3 M/s.