Question

masteryconnect wilson, makyla dtal - ch - term 1 - unit 2 assessment 25 - 26 radioactive iodine - 131 has a half - life of eight days. the amount of a 200.0 gram sample left after 32 days would be 25.00 g 6.250 g 12.50 g 50.00 g

Explanation:

Step1: Calculate number of half - lives

$n=\frac{32}{8}=4$

Step2: Use half - life formula

$A = A_0\times(\frac{1}{2})^n$, where $A_0 = 200$ g and $n = 4$.
$A=200\times(\frac{1}{2})^4$
$A = 200\times\frac{1}{16}$
$A = 6.250$ g

Answer:

6.250 g