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The atomic structure is the foundation of understanding chemical and physical properties of matter. An atom, the smallest unit of an element that retains its identity, holds a central nucleus surrounded by a cloud of electrons. The nucleus, a dense core, is composed of protons and neutrons tightly bound together by nuclear forces.

In the vast emptiness of the atom, electrons, much lighter than protons or neutrons, move in regions called orbitals. The number of protons within the nucleus defines the atomic number and thus the type of element, while the combination of protons and neutrons gives the atomic mass. Moreover, it's the electrons' arrangement around the nucleus that determines an atom's chemical behavior and its ability to form bonds.

Protons, bearing the hallmark of positive charge, significantly contribute to the mass of an atom. With every proton carrying a charge of +1 in atomic units, they impose a strong influence within the nucleus.

The mass of a proton is approximately \(1.67262192 \times 10^{-27}\) kg. When describing electrical charge, we use the fundamental charge unit, the Coulomb, with protons possessing a charge of \(+1.60217663 \times 10^{-19}\) Coulombs. This positive charge balances the negativity of electrons and defines the atom's electrical neutrality when protons and electrons are equal in number.

Neutrons are the uncharged counterparts within the atomic nucleus. Despite their lack of charge, they play a crucial role in providing stability to atoms and influencing their isotopic identity. Neutrons have a slightly greater mass than protons at approximately \(1.674927498 \times 10^{-27}\) kg.

The absence of charge in neutrons, measured as 0 Coulombs, enables them to act as a buffer within the nucleus, diminishing the repulsive forces between positively charged protons and thus stabilizing the atom's core.

Electrons are the agile particles of an atom, each carrying a negative charge that contrasts with the positivity of protons. These minuscule particles have a mass that is negligible compared to that of protons and neutrons, at approximately \(9.10938356 \times 10^{-31}\) kg.

Each electron holds a charge of -1 in atomic units, which translates to \(1.60217663 \times 10^{-19}\) Coulombs in the more familiar term. It's this charge that engages in chemical reactions as electrons are exchanged or shared between atoms, leading to compounds and the rich variety of matter we observe.