Problems 297- Which species in each of the pairs in Problem 29 is the stronger base?
- We saw in Chapter 6 that ethyne reacts with an equivalent amount of HCl to form vinyl chloride. In the presence of excess HCl, the
final reaction product is 1,1-dichloroethane. Why is 1,1-dichloroethane formed rather than 1,2-dichloroethane? - Why is the resonance energy of pyrrole greater than the resonance energy of furan
- Rank the following compounds in order of decreasing acidity of the indicated hydrogen:
- Explain why the electrophile adds to the carbon bonded to the greater number of hydrogens in reaction a, but not in reaction b.
a. b. - The acid dissociation constant for loss of a proton from cyclohexanol is
a. Draw an energy diagram for loss of a proton from cyclohexanol.
b. Draw the contributing resonance structures for phenol.
c. Draw the contributing resonance structures for the phenolate ion.
d. Draw an energy diagram for loss of a proton from phenol on the same plot with the energy diagram for loss of a proton from
cyclohexanol.e. Which has a greater cyclohexanol or phenol?
f. Which is a stronger acid, cyclohexanol or phenol?- Protonated cyclohexylamine has a Using the same sequence of steps as in Problem 35, determine which is a
stronger base, cyclohexylamine or aniline. - Answer the following questions for the molecular orbitals of 1,3,5,7-octatetraene:
a. How many MOs does the compound have?
b. Which are the bonding MOs and which are the antibonding MOs?
c. Which MOs are symmetric and which are asymmetric?
d. Which MO is the HOMO and which is the LUMO in the ground state?
e. Which MO is the HOMO and which is the LUMO in the excited state?
f. What is the relationship between HOMO and LUMO and symmetric and asymmetric orbitals?
g. How many nodes does the highest-energy molecular orbital of 1,3,5,7-octatetraene have between the nuclei?p
ppNH 3 NH 2 + H+NH 3 NH 2 + H+++Ka= 1 * 10 -^11.Ka,OH O− + H+Ka = 1 × 10 −^16
OH O− + H+1 Ka 2 1 * 10 -^16.CH 2 CHF + HF CH 3 CHF 2 CH 2 CHCF 3 + HF FCH 2 CH 2 CF 3sp^2OOCH 3 CCH 2 CH 2 CCH 3OOCH 3 CCH 2 CH 2 CH 2 CCH 3OOCH 3 CCH 2 CCH 3furan pyrroleN
HO(21 kcal>mol) (16 kcal>mol)?HC CH H 2 CCHCH 3 CHCl 2ClHCl HClBRUI07-263_297r4 21-03-2003 11:32 AM Page 297