CAS CH 102 Lecture Notes - Lecture 31: Valence Electron, Atomic Mass, Atom
Document Summary
Atomic structure and components: electrons revolve in orbitals around the nucleus: electrons. Valence electrons: electrons found in outermost energy level: nucleus: accounts for most of the mass of an atom, densely packed bundle of matter with positive charge. Particles in the nucleus are called nucleons. Cannot account for total mass of nucleus. Accounts for the rest of the mass of the nucleus: energy levels and shells: specific spherical orbits containing electrons. Closer to a nucleus, the less energy an electron needs in the level. Needs to gain energy to go to a level farther away from the nucleus. Needs to lose energy to go to a level closer to the nucleus. Atoms attempts to have a complete energy level. Called a stable octet; an atom will borrow, lend or share electrons to complete it: classification. The fewer electrons an atom tends to gain, lose or share, the more reactive it is.
