.) Iodine 131 is a radioactive waste product generated in nuclear power plants. It has a half life of 8 days. If 16 grams was released from the Fukushima power plant 32 days ago, how much is left now?
To determine how much Iodine-131 is left after 32 days, we need to understand the concept of radioactive decay and use the half-life of Iodine-131.
The half-life of a radioactive substance is the time it takes for half of the initial quantity to decay. In this case, the half-life of Iodine-131 is 8 days. This means that after 8 days, half of the Iodine-131 will have decayed, and after another 8 days, half of what was remaining will have decayed, and so on.
Now, let's calculate how many half-lives have occurred in 32 days. Since the half-life of Iodine-131 is 8 days, we divide 32 by 8:
32 days / 8 days = 4 half-lives
This means that after 32 days, 4 half-lives of Iodine-131 have occurred.
To find out how much Iodine-131 is left now, we can use the decay equation:
Amount remaining = Initial amount x (1/2)^(number of half-lives)
The initial amount of Iodine-131 released was 16 grams. Let's calculate the amount remaining:
Amount remaining = 16 grams x (1/2)^(4 half-lives)
Amount remaining = 16 grams x (1/2)^4
Amount remaining = 16 grams x (1/16)
Amount remaining = 1 gram
Therefore, after 32 days, only 1 gram of Iodine-131 is left from the initial 16 grams that were released from the Fukushima power plant.