The structure of an atom consists of three main subatomic particles: protons, neutrons, and electrons. Here's a brief overview: Protons: Positively charged particles found in the nucleus of an atom. Each proton carries a charge of + 1 +1 and has a mass of approximately 1 1 atomic mass unit (amu). Neutrons: Neutral particles found in the nucleus of an atom. Neutrons carry no electrical charge (they are electrically neutral) and also have a mass of approximately 1 1 amu, similar to protons. Electrons: Negatively charged particles that orbit the nucleus in specific energy levels or shells. Electrons are much smaller in mass compared to protons and neutrons, with a mass of approximately 1 / 1836 1/1836 amu. They are involved in chemical reactions and determine the chemical properties of an element. The nucleus, consisting of protons and neutrons, is located at the center of the atom and contains most of the atom's mass. Electrons, which have a much smaller mass, orbit around the nucleus in regions called electron shells or energy levels. These shells are arranged in a specific pattern depending on the atom's atomic number, giving rise to the atom's electronic configuration.