Say you have a rock composed entirely of potassium-40. After two half-lives of potassium-40, what fraction of the rock is still
1 answer:
<u>Answer:</u> The fraction of the rock that is still composed of potassium-40 is 0.25
<u>Explanation:</u>
To calculate the fraction of the rock that is still composed of K-40, we use the formula:
where,
a = amount of reactant left after n-half lives
= Initial amount of the reactant
n = number of half lives = 2
Putting values in above equation, we get:
Hence, the fraction of the rock that is still composed of potassium-40 is 0.25
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