reactions are processes in which one or more nuclides are produced from a collision between
two nuclei or one nucleus and a subatomic particle.
a. Chemical
b. Nuclear

Nuclear reactions are fascinating processes often observed in the core of stars or during radioactive decay. They involve interactions that change the composition and energy states of atomic nuclei, resulting in the formation of different nuclides, which can lead to the release of energy in significant amounts. In these reactions, conditions like temperature and pressure can be mind-boggling, especially when you think about fusion occurring at millions of degrees in the sun!

In contrast, chemical reactions involve the rearrangement of atoms and the making or breaking of chemical bonds, but the nuclei remain unchanged. This is why chemical reactions typically involve lower energy changes than nuclear reactions. Understanding the distinction can help visualize the different scales and the vast energies at play, whether in creating a new element or simply changing a molecule!