Question

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

Answer 1

ANSWER

67 grams

EXPLANATION

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

$N(t)=N_0\left(\frac{1}{2}\right)^{t/h}$

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,

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

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