CELL 1010 Lecture Notes - Lecture 2: Electric Field, Chemical Polarity, Octet Rule
Document Summary
Shells and orbitals: orbit: the path the electron takes, orbital: the space around the nucleus with the highest probability of finding an electron. N s = spin, p = principal, d = diffuse, f = fundamental. Energy shell: grouping of electrons surrounding the nucleus of an atom. Columns (groups): same number of valence electrons: elements in the same group have identical chemical characteristics. Covalent bonds: strongest types of bonds in biology; flexible (nonpolar) covalent bonds: equal sharing of electrons between atoms. Fulfills octet rule, so there"s no charge and no free electrons. Polar covalent bonds: unequal sharing of electrons: creates partial negative and positive charge on atoms due to difference in electronegativity between the atoms sharing the electrons. Electronegativity: a measure of an atom"s capacity to draw a bonded electron to itself. Ionic bonds: attraction between an anion and a cation/direct transfer of electrons from one atom to another.