the half-life of iodine-131 is 8 days. how much iodine-131 will be left after 8 days if you have an initial mass of 1g ?

Hmmm. The half life is eight days, and you have it for eight days, one halflife. Is half remaining?

0.5

To determine how much iodine-131 will be left after 8 days with an initial mass of 1g, you need to understand the concept of half-life.

The half-life of a radioactive substance is the amount of time it takes for half of the substance to decay or disintegrate. In this case, the half-life of iodine-131 is 8 days. This means that after 8 days, half of the initial amount will have decayed.

To calculate the amount of iodine-131 remaining after 8 days, we can use the following formula:

Amount remaining = Initial amount * (1/2)^(time elapsed / half-life)

In this case, the initial amount is 1g, the time elapsed is 8 days, and the half-life is 8 days. Plugging in these values into the formula, we get:

Amount remaining = 1g * (1/2)^(8/8)
= 1g * (1/2)^1
= 1g * (1/2)
= 0.5g

Therefore, after 8 days, there will be 0.5g of iodine-131 left.