Element X decays radioactively with a half life of 15 minutes. If there are 400 grams of Element X, how long, to the nearest tenth of a minute, would it take the element to decay to 87 grams?
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Answer:
The time it'd take for the element to have 15 g of mass is approximately 68 min.
Step-by-step explanation:
The radioactive decay of a substance is given by the following formula:
Since the element has a half life of 12 minutes, this means that after this time the mass of the element will be half of it was originally, therefore:
Therefore the mass of the element is given by:
If the initial mass is 760 g and the final mass is 15 g, we have:
The time it'd take for the element to have 15 g of mass is approximately 68 min.
Step-by-step explanation: