Exam 2 study guide
Exam 2 study guide CHEM 1111
Popular in General Chemistry I
Popular in Chemistry
This 2 page Study Guide was uploaded by Olivia SaoBento on Friday October 16, 2015. The Study Guide belongs to CHEM 1111 at George Washington University taught by Besson, C in Fall 2015. Since its upload, it has received 72 views. For similar materials see General Chemistry I in Chemistry at George Washington University.
Reviews for Exam 2 study guide
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 10/16/15
Exam 2 outline as given by instructor Naming ions and molecules 0 Ions 1 2 3 o Covalent Molecules Diff in electronegativity X gt 2 ionic bonds Metalcation 1st Cation anion ide 0 Sodium chloride Number Prefix 1 Xlt16 sum Xgt4 1 Mom 2 Xlt16 Sum Xlt4 metalic bonds 2 Di 3 Prefixatom Prefixatomide 3 TH 0 Nitrogen monoxide 4 Tetra o Dinitrogen tetroxide 5 penta Know common ions 6 Hexa 7 Hecta Lewis dot structures 8 Octa o Octet Rule atoms will lose or gain e to achieve 8 e 9 Nona 0 Exception HHe only want 2 e 10 Deca 1 2 3 Place dashes on outside atoms 1st to fulfill octet rule if octet not fulfilled Draw skeleton of molecule Count valence e introduce multiple bonds 0 Formal charges 1 2 3 Cut bonds in half Count lone pairs and half bonded pairs Compare to valence e more less 0 Sum of formal charges charge of molecule 0 Overall rules of determining Lewis structures 1 2 3 o Resonance two structures have same number of e pairs but placed differently 1 2 Octet rule Avoid formal charges if possible Put charge on the most electronegative atom Significant follows as many rules as possible Nonsignificant not best configuration 0 Exceptions to octet rule Incomplete octet less e9 Li Be Mg B Al and all that follow suit missing 1 3 pairs of e Incomplete octet odd 9 molecules odd number of e central atom can have less e than needed 8 May have 75 NEVER 9 Expanded octet only 3rel period and below VSEPR molecular geometry 0 AXnEm 1 Acentral atom 2 X neighboring atoms 3 E lone pairs around central atom o Bondse will try to be as far apart as possible 0 Lone pair gt bonding pair gt single e in terms of repulsion 0 Parent geometry AXnm know parent geometry and real geometry composition by mass 0 Molecular mass sum of atomic masses g o Molar mass mass of a mole of molecule gmol Molar mass of element 100 0 com b mass total molar mass of molecule 0 p y o If given percent s of each element 1 Assume a 100g sample percent s become mass g 2 Use formula to find moles mass 2 moles Molar mass 3 Divide each value by the lowest number of moles 4 These whole numbers are the subscript for each element 5 Use knowledge of cation v anion and common ions to determine Molecular formula Molecular Orbital o Bonding constructive interaction overlap of black to black andor white to white 0 Antibonding destructive interaction black to white 1 Stabilization bonding energy is smaller than destabilization antibonding 0 Axial symmetry 6 bonds 0 Lateral overlap Tl bonds 1 TI bonda have smaller stabilizationdestabilization energy e in bonding orbitals e in antibonding orbitals 2 0 Bond order 2 o Magnatism 1 Paramagnetic molecule with unpaired electrons 2 Diamagnetic molecules with all e paired Last exam material E o E hv l1 o c 2 Av COMMON ERRORS TO AVOID Formal charges must be included in all Lewis Structures Atoms do not move between resonance structures of e do o If resonance structures are not significant do not add if present denote or cross out Remember exceptions to octet
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'