# Organic Chem how electrons in an atom are distributed

 The flashcards below were created by user stalnakern11 on FreezingBlue Flashcards. The behavior of each electron in an atom can be described by a wave equation. Solution? The solution to the wave equation is orbitals. Orbitals tell us the energy of the electron and the volume of space around the nucleus where and electron is most likely to be found. NOTE: The elctrons in an atom can be thought of as occupying a set of concentric shells that surround the nucleus. The first shell is the closest, the 2nd shell is farther away and so on and so forth. Each shell has subshells known as atomic orbitals. A maximum of 2 electrons can coexist in an atomic orbital. Each atomic orbital has a characteristic shape and energy and occupies a characteristic volume of space. REMEMBER: the closer the atomic orbital is to the nucleus, the lower is its energy First Shell Consists of only 1 s atomic orbitalCan contain no more than 2 electrons Second Shell Consists of 1 s and 3 degenerate (orbitals that have the same energy) p orbitalsCan contain no more than 8 electrons Third Shell Consists of 1 s, 3 degenerate p, and 5 degenerate d orbitals.Can contain no more than 18 electrons Fourth Shell Consists of 1 s, 3 degenerate p, 5 degenerate d, and 7 degenerate f orbitals.Can contain no more than 32 electrons Aufbau principle An electron always goes into the available orbital with the lowest energy. REMEMBER: the closer the atomic orbital is to the nucleus, the lower is its energy. So a 1s orbital is lower in energy than a 2s orbital because the 1s orbital is closer to the nucleus. Pauli Exclusion Principle No more than two electrons can occupy each atomic orbital The two electrons must be of opposite spin It is called the exclusion principle because it limits the number of electrons that can occupy any particular shell From these first two rules, we can assign electrons to atomic orbitals for atoms that contain one, two, three, four, or five electrons. For atoms containing 6 or more electrons, we need Hunds rule: when there are degenerate orbitals-two or more orbitals with the same energy- an electron will occupy and empty orbital before it will pair up with another electron. This way, electron repulsion is minimized. (pg 7 in book) Core electrons Found in inner shellsDo not participate in chemical bonding Valence Electrons Found in the outermost shellElements in the same column of the periodic table have the same number of valence electrons Authorstalnakern11 ID127068 Card SetOrganic Chem how electrons in an atom are distributed Descriptionnotes Updated2012-01-11T01:42:46Z Show Answers