Question

How many decay product atoms will be present in the rightmost sample, after two half-lives have passed?

Answer 1

Since Half-life has to do with the decay of half of the amount of an atom, after two half-lives, we will end up with 2 of quantity of Hg-207, since we have started with 8 particles, and after one half-life we will have 4, therefore the last one will have only 2 particles of Hg-207