Element X decays radioactively with a half life of 5 minutes. If there are 340 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to decay to 4 grams?

32.0 min

Step-by-step explanation:

The equation that describes the decay of a radioactive isotope is:

(1)

where:

is the mass of the element at time t = 0

is the mass of the element left at time t

is the decay constant

The decay constant is related to the half-life of the element by

where

is the half-life

For element X, we have

So the decay constant is

We also know that for element X:

is the initial mass

is the final mass

So, from eq(1) we can now find the time:

idk

step-by-step explanation: