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Which of the following terms best describes the pair of compounds shown below?      

The compounds below are base pairs used to form supramolecular polymers. They are held together by three intermolecular hydrogen bonds and each contains one intramolecular hydrogen bond.  Which atom in structure B forms a hydrogen bond with the circled hydrogen in structure A?      

Which of the following pairs of bases lists the stronger base first? A. I- > Cl- B. O2 > HO- C. HO- > H2N- D. CH3COO- > HO- E. H2N- > CH3COO-

Which of the following series contains a free radical, a nucleophile, a carbene, and an electrophile (not necessarily in order)?  

The heat of combustion of 2,2-dimethylpropane is 3250 kJ/mol while the heat of combustion of pentane is 3269 kJ/mol. Which statement best describes the relative stability of these two compounds?  

The regiochemistry of hydroboration/oxidation of terminal alkynes is:

For the following problem, use a separate sheet of paper for your answer and then upload your answers at the following link: https://canvas.dccc.edu/courses/28473/assignments/574397 Your work must be shown for full credit.     A C6H12hydrocarbon (A) reacts with 1 molar equivalent of H2 over a palladium catalyst. Hydrocarbon (A) also reacts with OsO4 in pyridine to give diol (B). When oxidized with KMnO4 in acidic solution, (A) gives two fragments – a carboxylic acid (C) and another fragment (D). Draw the structures for A, B, C, and D and show how you arrived at your answers using chemical equations.

Which of the following is not a possible termination step in the free radical chlorination of methane?  

Which is the order from the weakest acid to the strongest acid for these species? Strongest on the right. I    CH3OH II   CH3OH2+ III  CH3NH2 IV  CH3NH3+  

For the following problem, use a separate sheet of paper for your answer and then upload your answers at the following link: https://canvas.dccc.edu/courses/28473/assignments/574397 Your work must be shown for full credit.     A C8H14 hydrocarbon (A) is reduced by sodium in liquid ammonia to a single C8H16 product (B). Both compounds undergo hydrogenation (using a Pt catalyst) to give 2,5-dimethylhexane. Ozonolysis of B followed by oxidative workup with H2O2 produces a single C4H8O2 carboxylic acid. Reaction of B with peroxybenzoic acid (C6H5CO3H) gives a chiral C8H14O product (C), but reaction with bromine gives an achiral C8H14Br2 product (D). Draw the structures for A, B, C, and D and show how you arrived at your answers using chemical equations.