Question

Iodine 131 has a half life of 8 days. If you start with a sample of 100 grams, how much iodine 131 would be left after 10 days. (3 points)

Answer 1

The half-life of Iodine-131 is 8 days, which means that after each 8-day period, the amount of Iodine-131 will be reduced by half.

After 8 days, half of the original amount will be left:
100 grams / 2 = 50 grams

After another 8 days (total of 16 days), half of the remaining amount will be left:
50 grams / 2 = 25 grams

After another 8 days (total of 24 days), half of the remaining amount will be left:
25 grams / 2 = 12.5 grams

Since 10 days is less than the first half-life of 8 days, we can assume that only one half-life has occurred. Therefore, after 10 days, half of the original amount will be left:
100 grams / 2 = 50 grams

So, after 10 days, there will be 50 grams of Iodine-131 left.