Chem 261 1nd Edition Lecture 2 Outline of Last Lecture I. Formal ChargeII. Constitutional IsomersIII. Condensed StructuresIV. Syllabus OverviewOutline of Current Lecture I. Atomic StructureII. Electron ConfigurationIII. Atomic OrbitalsCurrent LectureAtoms - the basic unit of a chemical element.Isotopes – each of two or more forms of the same element that contain equal numbers of protons but different numbers of neutrons in their nuclei, and hence differ in relative atomic mass but not in chemical properties; in particular, a radioactive form of an element.Atomic mass – It is approximately equivalent to the number of protons and neutrons in the atomPauli Exclusion – The Pauli Exclusion Principle states that, in an atom, no two electrons can have the same four electronic quantum numbers. We are aware that in one orbital a maximum of two electrons can be found and the two electrons must have opposing spins. That means one would spin up ( +1/2) and the other would spin down (-1/2).Aufbau – As we write the electron configuration for an atom, we will fill the orbitals in order of increasing atomic number.Hund’s – Hund's rule: every orbital in a subshell is singly occupied with one electron before any one orbital is doubly occupied, and all electrons in singly occupied orbitals have the same spin.Energy Diagrams with orbitals - Fill lower energy first, then proceed up* Definitions thanks to Google and Chem wiki. Picture everythingscience.comThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a