Question

A 40 gram sample of substance that's used for drug research has a k value of 0.1472

Answer 1

The substance's half-life in days is 4.7935 days

What is expression for exponential decay?

The expression that describes exponential decay:

$N(t) = N_o e^{-kt}$

Where N(t) is the mass of the substance after a period t of time.

No is the original amount of substance.

k is the relative decay rate and t is the period of time elapsed.

We can isolate t in the expression:

$\dfrac{N(t)}{ N_o} = e^{-kt}$

ln($\dfrac{N(t)}{ N_o}$) = -kt

t = - ln($\dfrac{N(t)}{ N_o}$) /k

t = - ln($\dfrac{N(t)}{ N_o}$) /0.1446

t = 4.7935 days.

The substance's half-life in days is 4.7935 days

Learn more about  half-life;

https://brainly.com/question/10734147

The complete question is

"a 40 gram sample of a substance that's used for drug research has a k-value of 0.1446. find the substance's half life in days."

#SPJ1