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How much of a radioactive kind of radium will be left after 49 hours ifthe half-life is 7 hours and you start with 8,576 grams of radium?label optional

User Jared Dunham
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1 Answer

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21 votes

ANSWER

67 grams

Step-by-step explanation

The half-life of a substance is found with the formula,


N(t)=N_0\left((1)/(2)\right)^(t/h)

Where N₀ is the initial amount of substance, h is the half-life, and t is the total time.

In this case, N₀ = 8,576 grams, h = 7 hours, and t = 49 hours,


N(49)=8,576g\cdot\left((1)/(2)\right)^(49/7)=\frac{8,576\text{ }g}{2^7}=67\text{ }g

Hence, the remaining amount of radium after 49 hours is 67 grams.

User Gudrun
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