chromium-48 decays and goes through 4 half-lives. how many grams would remain if you started with 100 grams ?

Answer 1

Hey Natalie,

A half-life is the time it takes something undergoing radioactive decay to have half of its starting mass decay. In this problem, we are given that we go through 4 half-lives. We can model the half-life masses like this:

100g/2= 50g (1st)

50g/2= 25g (2nd)

25g/2= 12.5g (3rd)

12.5g/2= 6.25g (4th)

Another way to do this instead of calculating each step is to take the original mass (100g) and divide by

2^half-lives. Doing so, we get:

100g/(2^half-lives)=

100g/(2⁴)=

100g/16= 6.25g

Hope this helps!