Final answer:
The rate constant of the reaction in a first-order decomposition reaction can be determined using the integrated rate law. In this case, the rate constant is approximately -0.0665 min^-1.
Step-by-step explanation:
In a first-order decomposition reaction, the rate of the reaction is proportional to the concentration of the compound. We can use the integrated rate law for first-order reactions to determine the rate constant. The integrated rate law for a first-order reaction is ln(A/A0) = -kt, where
A is the concentration at time t, A0 is the initial concentration, k is the rate constant, and t is the time elapsed. In this case, we know that 50.0% of the compound decomposes in 10.5 minutes. Since 50.0% of the compound decomposes, the concentration at time t is 50.0% of the initial concentration. Plugging in the values into the integrated rate law, we have ln(0.5) = -k(10.5). Solving for k, we find that the rate constant is approximately -0.0665 min-1 (rounded to four decimal places).