select the correct answer.\nif two half - lives have passed since a scientist collected a 1.00 - gram sample…

select the correct answer.\nif two half - lives have passed since a scientist collected a 1.00 - gram sample of u - 235, how much u - 235 is left now?\na. 0.001 g\nb. 0.100 g\nc. 0.250 g\nd. 0.450 g\ne. 3.00 g

select the correct answer.\nif two half - lives have passed since a scientist collected a 1.00 - gram sample of u - 235, how much u - 235 is left now?\na. 0.001 g\nb. 0.100 g\nc. 0.250 g\nd. 0.450 g\ne. 3.00 g

Answer

Explanation:

Step1: Calculate the remaining amount after one half - life

The formula for the remaining amount of a radioactive substance after (n) half - lives is (N = N_0\times(\frac{1}{2})^n), where (N_0) is the initial amount and (n) is the number of half - lives. For (n = 1), (N_1=1.00\times\frac{1}{2}= 0.50\space g)

Step2: Calculate the remaining amount after two half - lives

For (n = 2), (N_2=0.50\times\frac{1}{2}) [N_2 = 1.00\times(\frac{1}{2})^2=1.00\times\frac{1}{4}=0.250\space g]

Answer:

C. (0.250\space g)