The half-life of radioactive iodine is 60 days. How much of a 50-mg sample will be left in 40 days? Round your answer to the nearest tenth.

Remaining amount of the element = 31.5 mg

Step-by-step explanation:

Half life of radioactive Iodine is = 60 days

Formula to get the remaining element after t days is,

Where = decay constant of the radioactive element

t = duration of the decay (in days)

= Initial amount of the element

N = final amount after decay

For half life period 't' = 60 days

Remaining amount of the element after 40 hours,

N =

   =

   = 50(0.62996)

   = 31.49

   ≈ 31.5 mg

Therefore, remaining amount of the element after 40 days is 31.5 mg.