Chem 330 Exam 1 Questions And Answers All Correct

in an acid-base reaction, does the equilibrium favor the side of the weaker or stronger acid? - Correct Answers equilibria favor the reaction side with the lowest-energy species, acid-base reactions will go to the side with the WEAKEST acids and bases resonance structures - Correct Answers two forms of a molecule where the chemical connectivity is the same but the electrons are distributed differently around the structure. Resonance occurs when electrons can flow through neighboring pi systems - you cannot change the total charge when drawing resonance structures - same atoms connected in the same order constitutional isomers - Correct Answers compounds that have the same molecular formula and different connectivity. To determine whether two molecules are constitutional isomers, just count the number of each atom in both molecules and see how the atoms are arranged 3 questions for knowing if resonance is a possibility: - Correct Answers1) can we convert any lone pairs into pi bonds without violating the two commandments? 2) can we convert any pi bonds into lone pairs without violating the two commandments? 3) can we convert any pi bonds into pi bonds without violating the two commandments? 5 patterns to recognize in resonance structures: - Correct Answers1) a lone pair next to a pi bond - shift lone pair to form pi bond, shift pi bond to form lone pair 2) a lone pair next to a positive charge - shift lone pair to form a pi bond 3) a pi bond next to a positive charge - push double bond over (charge switches) 4) a pi bond between two atoms, where one of those atoms is electronegative -move pi bond up onto the electronegative atom to become a lone pair 5) pi bonds going all the way around a ring 3 rules for determining which resonance structures are significant: - Correct Answers1) minimize charges 2) electronegative atoms (N, O, Cl, etc.) can bear a positive charge but only if they possess an octet of electrons 3) resonance structures in which two carbon atoms bear opposite charges are generally insignificant rules for naming/numbering substituents: - Correct Answers1. If ONE substituent is present, number the parent chain so that the substituent has the lowest number possible 2. When multiple substituents are present, number the parent chain to give the first substituent the lowest number possible 3. If there is a tie, then number the parent chain so that the second locant gets the lowest number possible 4. If there is no other tie-breaker, then assign the lowest number alphabetically 5. The same rules apply for cycloalkanes 6. To assemble the complete name, assign a locant to each substituent, and list them before the parent chain name in alphabetical order 7. A prefix is used (di, tri, terta, penta, etc.) if multiple substituents are identical 8. Prefixes are NOT used for alphabetical purposes, except for the prefix "iso" do acids give or receive protons? - Correct Answersgive - strong acid is VERY willing to give up a proton do bases give or receive protons? - Correct Answersreceive which is more stable, a localized or delocalized charge? - Correct Answersdelocalized ARIO - Correct AnswersA - atom (electronegativity increasing to the right in a row, and SIZE increasing down a column) R - resonance (more delocalized charge = more stable charge, a charge spread over 4 atoms is more stable than a charge spread over 1 atom, one oxygen is better than many carbon atoms) - the more acidic proton is the one that leaves to form the more stable conjugate base I - induction (nearby electronegative atoms spread/stabilize charge) O - orbitals (negative charge on an sp orbital is more stable than a negative charge on an sp2 orbital is more stable than a negative charge on an sp3 orbital... closeness to nucleus stabilizes) electronegativity measures - Correct Answersan atom's affinity for