Scelta multipla
How much of a radioactive parent isotope will remain after three half-lives have passed?
668
views
15. Chemical Kinetics
Half-Life
Scelta multipla
After 5 half-lives have passed for 87Rb, what percentage of daughter isotopes would be present?
A
87.5%
B
50%
C
75%
D
96.9%
Guida verificata passo dopo passo1
Understand that after each half-life, half of the remaining parent isotope decays into the daughter isotope. The fraction of the parent isotope remaining after n half-lives is given by the formula: \(\left(\frac{1}{2}\right)^n\).
Identify the number of half-lives passed, which is 5 in this problem. Substitute n = 5 into the formula to find the fraction of the parent isotope remaining: \(\left(\frac{1}{2}\right)^5\).
Calculate the fraction of the parent isotope remaining after 5 half-lives, which represents the amount of 87Rb still present.
Determine the fraction of daughter isotopes formed by subtracting the fraction of the parent isotope remaining from 1: \(1 - \left(\frac{1}{2}\right)^5\).
Convert the fraction of daughter isotopes to a percentage by multiplying by 100 to find the percentage of daughter isotopes present after 5 half-lives.
Video correlati
Pratica correlata
