Question

After 40.0 min,

25.0%
of a compound has decomposed. What is the half‑life of this reaction assuming first‑order kinetics?

Answer 1

To find the half-life of the reaction, we can use the formula t1/2 = (0.693 / k), where k is the rate constant. We can calculate the rate constant using the formula k = (ln(1 / 0.25)) / t. Substituting the given values, we can then calculate the half-life of the reaction.

Step-by-step explanation:

For a first-order reaction, the half-life can be determined using the formula:

t_1/2 = (0.693 / k)

where t_1/2 is the half-life and k is the rate constant. In this case, we know that after 40.0 min, 25.0% of the compound has decomposed. To find the rate constant, we can use the formula:

k = (ln(1 / 0.25)) / t

Substituting the given values, we get:

k = (ln(1 / 0.25)) / 40.0 min

After calculating the value of k, we can then substitute it into the first formula to calculate the half-life.