you have 1,312 grams of a radioactive kind of lanthanum. if its half - life is 93 minutes, how much will be…

Explanation:

Step1: Calculate number of half - lives

The number of half - lives $n=\frac{279}{93}=3$.

Step2: Use half - life formula

The formula for radioactive decay is $A = A_0\times(\frac{1}{2})^n$, where $A_0$ is the initial amount and $n$ is the number of half - lives. Here, $A_0 = 1312$ grams and $n = 3$. So $A=1312\times(\frac{1}{2})^3$.

Step3: Calculate the remaining amount

$A = 1312\times\frac{1}{8}=164$ grams.

Answer:

164