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Five (5) of the six (6) molecules shown below have something on common with respect to their stereochemistry. Select the one that is different.

Determine the absolute configuration (R/S) of the chiral centers or E/Z configuration of the alkenes indicated below (A-D). A: [configA] B: [configB] C: [configC] D: [configD]

Five (5) of the six (6) molecules shown below have something on common with respect to their stereochemistry. Select the one that is different.  

Trehalulose (shown below) is a sugar found in small amounts in honey. Answer the questions below about the structure of trehalulose. Which two (2) chair structures below represent the chair conformations of the six-membered ring of trehalulose? Enter your choices in alphabetical order: [chair1] and [chair2]. Which of the chair structures represents the enantiomer of the six-membered ring of trehalulose? [enant] What is the absolute configuration (R or S) of the chiral center indicated with an asterisk (*)? [RSconfig] 

Consider the hydrochlorination reaction shown below and answer the questions that follow. In this reaction, a “MAJOR PRODUCT” is formed, i.e. a product that is formed in preference to the other. Assuming that the major product is derived from the most stable possible carbocation intermediate, which of the following molecules (A-F) would be the MAJOR product? [major] A “MINOR PRODUCT” is also possible in this reaction, i.e. any possible product that is not the major product. Which of the following molecules (A-F) would be the MINOR product? [minor] Considering only the major product, how many stereoisomers are possible for this molecule? [stereomajor] Considering only the minor product, how many stereoisomers are possible for this molecule? [stereominor]

Select all molecules below that are optically active.  

Identify the isomeric relationship for each pair of molecules (A-D) below. Choose the most specific answer that you can in each case.

Select all possible carbocation intermediates that could form in the reaction shown below.

Testing Along with Luke’s strange behavior, he also begins having seizures. Luke’s parents are extremely concerned and call an ambulance and Luke is transport to the hospital.  At the hospital, samples of blood were taken and sent to various labs for testing. After he was sedated, Luke had a lumbar puncture procedure to remove a sample of cerebral spinal fluid (CSF), which was sent for culture and also for direct observation with a phase contrast microscope. While waiting for the results of his spinal tap, Luke’s doctors start him on antibiotics.  Question: With the information gathered at the hospital, Luke most likely has which of the following?

Sucrose (shown below) is a sugar produced mainly by plants and is refined to become table sugar. Answer the questions below about the structure of sucrose. Which two (2) chair structures below represent the chair conformations of the six-membered ring of sucrose? Enter your choices in alphabetical order: [chair1] and [chair2]. Which of the chair structures represents the enantiomer of the six-membered ring of sucrose? [enant] What is the absolute configuration (R or S) of the chiral center indicated with an asterisk (*)? [RSconfig]