4 Fundamental laws of Chemistry
Who were Pauli, Hund, and Aufbau?What are their contributions to modern atomic theory?

Objective: Draw accurate valence configurations and lewis dot structures for selected molecules ionic and covalent compounds and chemical equations .
The objective of this page is to help develope the understanding of the arrangement of an atom's elctrons and lewis dot structures for selected molecules, compounds with an electronegativity differecne of 1.7 or greater and between .4 and 1.7, and chemical equations. (worth ethic):student uses prior knowledge of 2 vocabulary words.

Pauli's, Hund's, and Aufbau's principles and rules help us to uncerstand how to accuratly develope a valence configurations for selected molecules and thier rules and principles about electrons became a big importance in the structure of matter and chemistry as a whole. - (Worth ethic):student connects this topic to another major dicipline, physics.

Pauli was a very bright child. He excelled in classical history, science, and mathematics. Just 1 year after graduating from high school he published three academic papers on general relativity. He was a theoretical physicist (Tolluch, David).He was one of the pioneers of quantum physics.
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Pauli's excluion principle states that an orbital or electron location may contain at most two electrons at opposite spends. No electrons can have the same adress. The s-orbital can hold 2 electrons. The p-orbitals can hold up to 6. The d-orbitals can hold up to 10.

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Aufbau's was also a very bright physicist.
Aufbau's principle states that elctrons enter the lowest possible principle energy 1st. It is used to determine the electron configuration of an atom. Each energy level is divided into sublevels.

Ex. external image orbitaldiagram.JPGexternal image carbon.gifhttp://www.ccs.k12.in.us/chsBS/kons/kons/images/carbon.gif

Hund was a german physicist.
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The Hund's rule states that electrons don't pair up until they have to. A sublevel in an orbital may not always have two electrons.

Ex. external image fig1_4.gif

The Law of Conservation of matter states that the product of a reaction will have the same mass as the reactants. No matter is loss nor gained.
The Law of conservation of matter allows you to write a correct chemical equation.

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The right side of a chemical equation must have the same mass as the left side of the chemical equation.

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Ex. If this sandwich were a product of a reaction the reactants would be 2 slices of bread, 8 slices of tomatoes, 1 slice of cheese, and 1 slice of lettuce.

Tulloch, David. "Wolfgang Pauli's Exclusion Principle." Science and Its Times: Understanding the Social Significance of Scientific Discovery. Eds. Josh Lauer and Neil Schlager. Vol. 6. Detroit: Gale, 2000. 4 pp. 8 vols. Gale Virtual Reference Library. Gale. Patrick F Taylor Science & Tech Academy. 12 Nov. 2009