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Carbon 15 has a half-life of 2.5 seconds. suppose you have a sample containing 100 mg of c 15. how much were made after 10 seconds

User Dunkley
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1 Answer

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Final Answer:

After 10 seconds, there will be 6.25 mg of C-15 remaining.

Step-by-step explanation:

Radioactive decay is a first-order process, which means that the rate of decay is proportional to the amount of radioactive material remaining. The half-life of a radioactive isotope is the time it takes for half of the original amount to decay.

The formula for radioactive decay is:

N(t) = N0 * e^(-kt)

where:

N(t) is the amount of radioactive material remaining at time t

N0 is the initial amount of radioactive material

k is the decay constant

t is the time

The decay constant for a radioactive isotope can be calculated using the following equation:

k = ln(2) / t1/2

where:

t1/2 is the half-life of the isotope

Plugging in the values for carbon-15, we get:

k = ln(2) / 2.5 s = 0.277 s^-1

Now we can use the formula for radioactive decay to calculate the amount of C-15 remaining after 10 seconds:

N(10 s) = 100 mg * e^(-0.277 s^-1 * 10 s) = 6.25 mg

Therefore, after 10 seconds, there will be 6.25 mg of C-15 remaining.

User Darronz
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