KS.2A. Chemistry: The student will develop an understanding of the structure of atoms, compounds, chemical reactions, and the interactions of energy and matter.
2A.1. The student will understand the structure of the atom.
2A.1.1. The student understands atoms, the fundamental organizational unit of matter, are composed of subatomic particles. Chemists are primarily interested in the protons, electrons, and neutrons found in the atom.
2A.1.2. The student understands isotopes are atoms with the same atomic number (same number of protons) but different numbers of neutrons. The nuclei of some atoms are radioactive isotopes that spontaneously decay, releasing radioactive energy.