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Rank the structures shown from most to least stable.

Given the bond dissociation energies below (in kcal/mol), estimate the ΔH° for the propagation step CH3CH2CH2—H                     98(CH3)2CH—H                           95Cl—Cl                                        58H—Cl                                       103CH3CH2CH2—Cl                       81(CH3)2CH—Cl                             80

What are the predicted products for the SN1 reaction shown?

Which choice shows the transition state for the given SN2 reaction?

Using the bond dissociation energies given, calculate ΔH° for the following reaction.   Bond A-B   ΔH° KJ/mol CH3CHICH2CH3 222 I-I 151 H-CH2CH2CH2CH3 397 H-I 297  

Select the word or phrase that complete each sentence (constitutional isomers, diastereomers, enantiomers, meso compounds, higher, lower, reaction, addition, carbocation, carbanion, nucleophile, electrophile, elimination, heterolysis, homolysis, reagent, substitution, stronger, weaker, charge, activation energy, enthalpy, entropy, catalyst, transition state, intermediate,  concerted, two step, SN1, SN2, E1, E2, racemization, hyperconjugation, alkyl halides, inversion):     A(An)…………………………….. speeds up the rate of a reaction by providing an alternative pathway with a lower energy of activation. Complete word/phrase and correct spelling (verbatim) is required. No partial credit.

Select the word or phrase that complete each sentence (constitutional isomers, diastereomers, enantiomers, meso compounds, higher, lower, reaction, addition, carbocation, carbanion, nucleophile, electrophile, elimination, heterolysis, homolysis, reagent, substitution, stronger, weaker, charge, concerted, two step, SN1, SN2, E1, E2, racemization, hyperconjugation, alkyl halides, inversion):     A(an) …………………………….. has an electron-deficient atom that is capable of accepting a pair of electrons. Complete word/phrase and correct spelling (verbatim) is required. No partial credit.

The motion picture, invented in 1889, developed as an important form of entertainment during the first decade of the 1900s. At first, the “nickelodeons,” as the early movie theaters were called, appealed mainly to a lower-class and largely ethnic audience. In 1902, New York City had 50 theaters; by 1908, there were more than 400 showing 30-minute dramas and romances. Not__________________ World War I, when D.W. Griffith produced long feature films did the movies begin to attract a middle-class audience.

The relative influence of a husband and wife on a particular consumer decision depends in part on the product category. ______________________, husbands often dominate the purchase of a new automobile, while the purchase of food and home furnishings is often wife-dominated.

President George W. Bush’s landmark education law, No Child Left Behind, required all schools to bring all students to high levels of achievement. But it ignored the fact that students from low-income households perform less well in school, on average than students from more affluent backgrounds.   Given the current political and economic climate, a significant effort to reduce poverty is not likely to happen. So what can be done?  Since they can’t take on poverty itself, education policy-makers should try to provide poor studentswith the social support and experiences that middle-class students take for granted: afterschool programs, summer camps, school-based health centers, and mentoring and enrichment services.  Other countries already pursue such strategies. In Finland, which boasts high-performing schools, schools provide food and free health care for students.   Developmental needs are addressed early. Counseling services are abundant.  Why can’t we do the same thing here in America?   The pattern of organization is ______________.