Question

The rate constant for the reaction is 0.800 at 200°C. If the initial concentration of A is 0.00320 M, what will the concentration after 855 seconds?

a) 0.00160 M
b) 0.00240 M
c) 0.00320 M
d) 0.00400 M

Answer 1

Without the order of the reaction, it's not possible to calculate the concentration of A after 855 seconds based on the given rate constant and initial concentration.

Step-by-step explanation:

To answer the question regarding the concentration of A after 855 seconds when the rate constant for the reaction is 0.800 at 200°C, we need additional information about the order of the reaction. The order of the reaction can greatly affect the calculation of the concentration over time. For first-order reactions, the concentration of a reactant decreases exponentially with time and is described by the equation ln[A] = -kt + ln[A]0, where [A] is the concentration at time t, k is the rate constant, and [A]0 is the initial concentration.

Similarly, for second-order reactions, the equation 1/[A] = kt + 1/[A]0 is used. Without knowing the order of the reaction, we cannot use the provided rate constant and initial concentration to determine the concentration after a certain period. Therefore, additional context or assumptions are needed to solve this problem.