Chromium-51 has a half life of 27.70 days. How much will be left after 166.2 days if

you started with a 924 gram sample? How much decayed?

O

14.44g left; 909.56g decayed

35.54g left; 888.46g decayed

'all of it decayed

14.44g left; 938.44g decayed

Respuesta :

Answer:

Decayed mass: 909.56 g, Left mass: 14.44 g.

Explanation:

The time constant of the Chromium-51 is:

[tex]\tau = \frac{t_{1/2}}{\ln 2}[/tex]

[tex]\tau = \frac{27.70\,days}{\ln 2}[/tex]

[tex]\tau = 39.963\,days[/tex]

The decay equation for the isotope has the following form:

[tex]\frac{m(t)}{m_{o}} = e^{-\frac{t}{\tau} }[/tex]

The total decay at a given instant t is:

[tex]\% \delta = \left(1-e^{-\frac{t}{\tau} } \right) \times 100\,\%[/tex]

The total decay at 166.2 days is:

[tex]\% \delta = 98.437\,\%[/tex]

Decayed mass: 909.56 g, Left mass: 14.44 g.