Question

A 33 gram sample of a substance that's used to detect explosives has a k-value of 0.1473.
What is the substance's half-life in days, rounded to the nearest tenth?

Answer 1

half-life = ln(2) / k
half-life = .693/0.1473
half-life = 4.7
would that be days ?

Answer 2

Does the k-value have any units?

Answer 3

Yes, Thanks for the help!