I would like to ask if it is possible to tell an anomer using Fischer projection (e.g. glucose). In high school we learned only Haworth and Tollens are hepful in this case.

However, I'm not exactly sure since normal or wedged bonds used in drawn Fischer projection should give the idea. If the double bonded oxygen is on the right that is where poloacetal hydroxyl group will be formed, should stay above the ring after cyclisation and based on normal/wedged bond connecting $\ce{-CH2OH}$ goup with the rest of the molecule one should be able to tell the anomer.

I feel like I am missing a very basic principle that causes any attempt of my logical explanation to fail.

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    $\begingroup$ Considering that Emil Fischer was the one who named the sugars, his projection is probably able to tell them apart... :) $\endgroup$ – Zhe Mar 3 '17 at 12:56
  • $\begingroup$ The problem with Fischer is that it is designed for linear compounds. An extension for cyclic ones does exist (specifically for anomers, in fact) but I forgot it. $\endgroup$ – Jan Mar 3 '17 at 22:42
  • $\begingroup$ For a mnemonic of pyranose anomers in the Fischer, Haworth and chair conformations, look here: ursula.chem.yale.edu/~chem220/chem220js/STUDYAIDS/… $\endgroup$ – user55119 Mar 7 '18 at 16:14

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