Question

If we start with 48 g of a radioactive substance with a 2 hour 12 life, how much is left after two half-lives?

four half-lives?

Answer 1

Step-by-step explanation:

Half-life is the time taken for a radioactive material to decay to half its original composition:

Original mass = 48g

Half- life = 2hr

After four half lives;

Initially: 48g

First halving 24

Second halving 12

Third halving 6

Fourth halving 3

After second half life, we would have 12g

At fourth halving, we would have 3g