Answer: 12 Protons, 12 electrons and 16 neutrons. The number of protons and electrons always stays the same, but the neutrons is the mass-protons. In this case, 28-12=16 neutrons.
The half life of this radioisotope is 12 hours.
<u>Explanation:</u>
The length of time it requires to break down for an initial half amount or the amount of time taken to transform half of a reactant into product. Half of a particular sample took the time to experience radioactive decay. The time it would take to degrade radioactively into another component or nuclide for half of the atoms of an unstable element or nuclide.
If 1/16 of the sample remains it predicts that there were 4 half-life periods then 16 = 2⁴
4 half-life periods = 48 hours / 4
half-life period = 12 hours.
