The half-life of Cu-61 is approximately 3 hours, meaning that after each half-life, half of the remaining sample decays. After 9 hours, which is three half-lives (3 hours x 3 = 9 hours), the original 2 mg sample would have gone through three decay cycles. Thus, the amount remaining would be (2 , \text{mg} \times \left(\frac{1}{2}\right)^3 = 2 , \text{mg} \times \frac{1}{8} = 0.25 , \text{mg}).
Copper-64 (Cu-64) has a half-life of approximately 12.7 hours. After one half-life (12.7 hours), half of the original sample would remain. Therefore, from a 2 mg sample, after 12 hours, approximately 1 mg of Cu-64 would remain, as it has not yet fully completed one full half-life.
0.25
1 mg
1 mg
1/8th of a mg. You lose half every three hours.
After 132 hours, 1/4 of the initial sample of 10 Ci of Mo-99 would remain. Since the half-life is 66 hours, after 66 hours half of the sample would remain (5 Ci), and after another 66 hours (totaling 132 hours), half of that remaining amount would be left.
Copper-64 (Cu-64) has a half-life of approximately 12.7 hours. After one half-life (12.7 hours), half of the original sample would remain. Therefore, from a 2 mg sample, after 12 hours, approximately 1 mg of Cu-64 would remain, as it has not yet fully completed one full half-life.
1 mg
0.25
1 mg
0.25 mg
1 mg
.25 mg
1 mg
1/8th of a mg. You lose half every three hours.
2.5
To determine the remaining amount of Molybdenum-99 after 132 hours, we can use the half-life formula. Since the half-life is 66 hours, after 132 hours (which is two half-lives), the initial sample of 10 Ci will be reduced by half twice. Thus, after the first half-life, 5 Ci remains, and after the second half-life, 2.5 Ci will remain.