CHEM 237 Final Exam Review TAMU Questions and Answers with Expert Verified Solutions

CHEM 237 Final Exam Review TAMU Questions and Answers with Expert Verified Solutions Which reagent is not an oxidizing agent? a. NaOCl b. KMnO4 c. K2Cr2O7 d. CrO3 e. H2O - ✔✔H2O Which statement is false about preparing alkyl halide from alcohol with hydrogen halide? a. it is an SN1 reaction b. tertiary alcohols react faster than secondary alcohols c. the intermediate is a carbocation d. alkyl halide is soluble in conc. HCl e. in the reaction, the slowest step is the formation of a carbocation - ✔✔alkyl halide is solub le in conc. HCl 2‐Chloro‐2‐methylpentane was treated with conc. NaOH to generate products of E2 elimination. If 12 grams of the alkyl halide was used and 6.2 grams of alkene product was obtained, what was the percent yield for the reaction? (Atomic weight s: C - 12; H - 1; Cl - 35.5) a. 70% b. 74% c. 52% d. 67% e. None of the above - ✔✔74% During the purification of allyl‐2‐naphthyl either in the phase transfer catalysis experiment, some products were retained the in the silica gel mini‐column. What is the nature of these retained products? a. non‐polar b. polar c. basic d. acidic e. none of the above - ✔✔polar In a thin layer chromatography experiment, a plate 24 cm long was employed and the solvent was allowed to rise 20 cm. Two spots were observed which had moved 8 cm and 12 cm. Their respective Rf values are: a. 0.33 and 0.50 b. 1.00 and 1.50 c. 0.67 and 1.00 d. 8.00 and 12.00 e. 0.40 and 0.60 - ✔✔0.40 and 0.60 In the distillation of hexane/heptane and hexane/octane mixtures, the early distillation fractions contain higher percentages of hexane because: a. hexane reacts with oxygen faster b. heptane and octan e sticks to the distillation vial c. hexane has a higher vapor pressure d. the vapors of heptane or octane escaped and did not condense e. heptane and octane have higher vapor pressures - ✔✔hexane has a higher vapor pressure IR Spectroscopy is useful in t he analysis of carbonyl compounds because: a. the carbonyl group is chiral b. carbonyl compounds are brightly colored c. the C=O bond is a strong absorber of particular frequencies of infrared radiation d. carbonyl groups emit characteristic frequencies of infrared radiation e. carbonyl rotational states are closely packed - ✔✔the C=O bond is a strong absorber of particular frequencies of infrared readiation Which of the following would be the reagent reacted with a secondary alcohol to produce a ketone? a. O3; Zn, H3O+ b. OsO4 c. LiAlH4 d. NaOCl + CH3CO2H e. Ag(NH3)2+ - ✔✔NaOCl + CH3CO2H Which of the following compounds would you expect to undergo an SN1 reaction with HCl the fastest? a. sp3 primary alcohol b. sp3 secondary alcohol c. sp3 tertiary alcohol d. sp2 secondary alcohol - ✔✔sp3 tertiary alcohol Which of the following statements about an SN1 Solvolysis Experiment is false? a. The reaction involves a single‐step mechanism. b. The solvent is the nucleophile. c. The reaction i s a first order reaction. d. A decrease in polarity of reaction mixture slows down the reaction. e. The rate constant k was determined without having to know the exact concentration of NaOH. - ✔✔The reaction involves a single -step mechanism. In the isolat ion of eugenol, a methylene chloride solution of clove oil was extracted with two 15‐mL portions of 3N NaOH. What should be done if a solid forms in the separatory funnel and doesn't allow a separation? a. add HCl to neutralize the excess NaOH b. add water to the funnel to dissolve the sodium salt of eugenol c. filter off the excess sodium salt of methylene chloride and continue with the separation d. add methylene chloride to the funnel to dissolve the eugenol