Answer:
7.5 grams
Step-by-step explanation:
From the question,
(R/R')ᵇ = 2ᵃ.................... Equation 1
Where b = half life, R = Original mass of iodine, R' = Remaining mass of Iodine after disintegration, a = Total time taken.
⇒ R/R' = 2ᵃ/ᵇ............... Equation 2
Given: R = 60 grams, a = 24 days, b = 4 days
Substitute these values into equation 2
60/R' = 2²⁴/⁸
60/R' = 2³
R' = 60/2³
R' = 60/8
R' = 7.5 grams