14C has a half-life of 5,730 years. If we start with 70 grams of 14C at time zero how many grams of 14C will be left after three half-lives?
To find out how many grams of 14C will be left after three half-lives, we need to understand how radioactive decay works.
The half-life of a radioactive substance is the time it takes for half of the sample to decay. In this case, the half-life of 14C is 5,730 years.
For each half-life, the amount of 14C remaining is halved. So after the first half-life, we would have 70 grams / 2 = 35 grams remaining.
After the second half-life, we would have 35 grams / 2 = 17.5 grams remaining.
And after the third half-life, we would have 17.5 grams / 2 = 8.75 grams remaining.
Therefore, after three half-lives, there would be approximately 8.75 grams of 14C left.