Question

Y=

2) lodine-131 has a half-life of about 8 days. Find the amount left
from a 30-gram sample after 40 days.

Answer 1

15/16 gram

Explanation:

40 days represents 40/8 = 5 half-lives. That is, the quantity remaining is (1/2)^5 = 1/32 of the original amount, so is ...

(30 g)/32 = 15/16 g