How many half-lives of radon-222 have passed in 11.46 days? if 5.2 × 10−8 g of radon-222 remain in a sealed box after 11.46 days, how much was present in the box initially socratic. org

(i) Approximately 3 half lifes

(ii)

Step-by-step explanation:

(i) ∵ The half life of Radon-222 is approximately 3.8 days,

So, the number of half life in 11.46 days = ≈ 3

(ii) Since, the half life formula is,

Where,

= initial quantity,

t = number of periods

= half life of the quantity,

Given,

N =

t = 11.46 days,

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