Question

(e) What will be the activity of a radioactive substance in
terms of the initial activity at the end of four half-lives?

Answer 1

Answer:

Radioactive decay reduces the number of radioactive nuclei over time. In one half-life t1/2, the number decreases to half of its original value. Half of what remains decay in the next half-life, and half of those in the next, and so on. This is an exponential decay, as seen in the graph of the number of nuclei present as a function of time.