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2 years ago

lodine-131 has a half life of about 8 days. If you had 60 grams of , how much would remain after 24 days?

Physics

1 answer:

prisoha [69]2 years ago

7 0

Answer:

7.5 grams

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

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