What is the half-life of 20 g of a radioactive sample if 5 g remain after 8 minutes?

Hello!

The half-life is the time of half-disintegration, it is the time in which half of the atoms of an isotope disintegrate.

We have the following data:

mo (initial mass) = 20 g

m (final mass after time T) = 5 g

x (number of periods elapsed) = ?

P (Half-life) = ? (in minutes)

T (Elapsed time for sample reduction) = 8 minutes

Let's find the number of periods elapsed (x), let us see:

Now, let's find the half-life (P) of the radioactive sample, let's see:

I Hope this helps, greetings ... DexteR! =)

the answer is 75.0%.