Respuesta :
The first step is to remember the equation for radioactive disintegration:
[tex]M(t)=\text{ M}_{0\text{ }}*\text{ }e^{\frac{-t\text{ * ln 2}}{T}}[/tex]Where M(t) is the mass of the atom at any time t, Mo is the initial mass of the element, and T is the half-life time.
In this case, we have to calculate M(t), which is the remaining mass of the radioactive element. We have all the data from the right part of the equation (initial mass Mo, the time t at we want to calculate the remaining mass, and the half-life T of the element):
[tex]\begin{gathered} M(8)=\text{ 150 g * }e^{\frac{-30\text{ d }*\text{ }ln\text{ 2}}{8\text{ d}}\text{ }} \\ M(8)=\text{ 11.1488 g} \end{gathered}[/tex]Then, the answer is that the remaining mass of iodine-131 is C. 11 g approx
