What are the uses of cork?

Question

laboratory apparatus

Answer 1

In a modern chemistry lab, about the only corks you see are in the Friday afternoon wine bottles.  Many labs have no cork at all.  The one place it is still used in some labs is for cork rings which hold round bottom flasks (see reference).  They make the best holders for these, even though plastic can be used.

In the past, anywhere you now see a rubber stopper or ground glass joint, a cork would have been used, but they are rarely seen today (starting 3rd reference)..