The rate constant,k,for a first-order reaction is equal to 4.2 × 10^-4 s^-1.What is the half-life for the reaction?

Question

Quizplus · Accepted Answer

The formula for calculating the half-life of a first-order reaction is:

t1/2 = (ln 2)/k

where k is the rate constant.

Plugging in the given value of k, we get:

t1/2 = (ln 2)/4.2 × 10-14 s-1

Using a calculator, we get:

t1/2 = 1.67 × 10^13 s

This can be expressed in scientific notation as:

t1/2 = 1.7 × 10^13 s

Therefore, the best choice is C: 1.7 × 10^13 s.

The Rate Constant,k,for a First-Order Reaction Is Equal to 4