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2 years ago

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Select the correct answer from the drop-down menu. a scientist digs up sample of arctic ice that is 458,000 years old. he takes

it to his lab and finds that it contains 1.675 grams of krypton-81. if the half-life of krypton-81 is 229,000 years, how much krypton-81 was present when the ice first formed? use the formula n = n0 . the ice originally contained grams of krypton 81.

1 answer:

Jlenok [28]2 years ago

8 0

The original mass of krypton 81 that is present in the ice is 6.70 grams.

<h3>How do we calculate original mass?</h3>

Original mass of any substance will be calculated as below for the decomposition reaction is:

N = N₀(1/2)ⁿ, where

N = remaining mass of krypton-81 = 1.675g

N₀ = original mass of krypton-81 = ?

n will be calculated as:
n = T/t, where

T = total time period = 458,000 years

t = half life time = 229,000 years

n = 458,000/229,000 = 2

Now putting all these values on the above equation, we get

N₀ = 1.675 / (1/2)²

N₀ = 6.70 g

Hence required mass is 6.70 g.

To know more about half life time, visit the below link:
brainly.com/question/2320811

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