An alpha particle consists of two protons and two neutrons. This makes it a helium nucleus.
1. The structure of an alpha particle is composed of two protons, which are positively charged particles, and two neutrons, which are neutral particles.
2. This configuration gives the alpha particle a positive charge due to the presence of the two protons.
3. Alpha particles are relatively large and heavy compared to other types of particles like beta particles or gamma rays, and they have a low penetration ability due to their size and charge.
4. When emitted from a radioactive nucleus during alpha decay, an alpha particle seeks to reach a more stable configuration by reducing the number of protons and neutrons in the parent nucleus.
Therefore, the correct answer is: C. two protons and two neutrons
