BIOLOGY 1A Lecture Notes - Lecture 1: Valence Electron, Ionic Bonding, Atomic Mass
Document Summary
Exchange of electrons of the outside orbitals is the basis of chemistry/biology/chem. reactions. Li: easier to donate its lone electron rather than receive 7 electrons. F: has 7 electrons on its outer orbital so it is easier to receive electrons. Sodium x f/cl (easier) to fill the outside orbitals: ionic bond positive & negative bond. Covalent bonds: sharing of electrons in the valence shell. Strongest bonds in biology (hard to break) Oxygen larger molecule pulls electrons and leave positive charge on the hydrogen & negative charge of oxygen. Hydrogens at an angle dipole molecule allows to orient with one another. Hydrogen bond: hydrogen participates in the bonding (not as strong as covalent bonds) ex. Ions: polar molecules, both, create hydration shell/sphere according to the positive or. Dissociation of protons/acid-base negative charge: highly reactive species (h+, oh-, h+, h3o+ hydronium ions, oh- hydroxide ion, ph= -log [h+, acid: 0-6 more h, neutral: 7, basic: 8-14 more oh-
