National League for Nursing (NLN) Science Practice Exam

Which of the following particles/rays is not a type of radioactive emanation?

1. alpha particle.

2. beta particle.

3. gamma ray.

4. carbon-12.

The correct answer is: carbon-12.

Carbon-12 is indeed the correct choice as it is a stable isotope of carbon and not a type of radioactive emanation. Radioactive emanations refer specifically to particles or rays that are emitted from the nucleus of an atom during radioactive decay. Alpha particles consist of two protons and two neutrons, essentially the nucleus of a helium atom, and are released during the decay of heavy elements. Beta particles are high-energy, high-speed electrons or positrons emitted by certain types of radioactive nuclei. Gamma rays are electromagnetic radiation of extremely short wavelength emitted from the nucleus during decay processes, often accompanying alpha or beta decay. In contrast, carbon-12 is a naturally occurring, stable isotope with a full complement of nucleons and does not undergo radioactive decay, thus it does not emit particles or rays in the way radioactive substances do. Understanding these distinctions is crucial in the study of nuclear chemistry and physics, as it highlights the differences between stable isotopes and radioactive materials.