A certain first-order reaction is 45.0% complete in 65 s. What are the values of the rate constant and the half-life for this process

0.01228s⁻¹ = rate constant

Half-life = 56.4s

Explanation:

The first order reaction follows the equation:

ln[A] = -kt + ln[A]₀

Where [A] is amount of reactant after time t = 45.0%, k is rate constante and [A]₀ initial amount of reactant = 100%

ln[45%] = -k*65s + ln[100%]

-0.7985 = -k*65s

0.01228s⁻¹ = rate constant

Half-life is:

Half-life = ln2 / k