Question

In a first order reaction the initial concentration of the reactant was \(0.1 \text{ M}\) at \(298 \text{K}\). It is decreased to \(0.01 \text{ M}\) in 8 minutes and 20 seconds. Calculate the rate constant of the reaction at \(298 \text{K}\).

• A. \(2.303 \times 10^{-3} \text{ s}^{-1}\)
• B. \(2.303 \times 10^{-4} \text{ s}^{-1}\)
• C. \(4.606 \times 10^{-4} \text{ s}^{-1}\)
• D. \(2.303 \times 10^{-5} \text{ min}^{-1}\)
• E. \(4.606 \times 10^{-3} \text{ s}^{-1}\)

Hint:

Always check the units of the options. Since the time includes seconds and the options are in \(s^{-1}\), convert the entire time duration to seconds immediately before starting the calculation.

Answer 1

Answer: (E)