BIO SCI 93 Lecture Notes - Lecture 2: Chemical Polarity, Electronegativity, Structural Formula

• School: UC-Irvine
• Department: Biological Sciences
• Course: BIO SCI 93
• Professor: Aimee Edinger

Document Summary

Lecture 2: molecules of life: water, carbohydrates, lipids, nucleotides, and buffers. First shell only holds maximum 2 electrons; 8 for each higher level shells. Electrons tend to stay exist at the lowest available state of potential energy. Electron shells - levels that electrons exist in. Valence electrons - electrons in the outermost shell. Concept 2. 2 an element"s properties depend on the structure of its atoms. Concept 2. 3 the formation and function of molecules depend on chemical bonding between atoms. Covalent bond - sharing valence electrons between atoms. Molecule - two or more atoms covalently bonded. Molecular formula - indicates what a molecule consists of. Lewis dot structure - element symbol surrounded by dots (represent valence electrons) Structural formula - draw lines in between element symbols to represent bonds. One line = single bond; two lines = double bond. Space-filling model - closest image of a molecule in 3d. Bonding capacity/atom"s valence - number of covalent bonds an atom can make*