What is a Buchner or filter flask and how is it used?
From Wikipedia.com (see Link to the left):A Büchner flask, also known as a vacuum flask, filter flask, side-arm flask or Kitasato flask, is a thick-walled erlenmeyer flask with a short glass tube and hose barb protruding about an inch from its neck. The short tube and hose barb effectively acts as an adapter over which the end of a thick-walled flexible hose (tubing) can be fitted to form a connection to the flask. The other end of the hose can be connected to source of vacuum such as an aspirator vacuum pump or house vacuum. Preferably this is done through a trap (see below), which is designed to prevent the suckback of water from the aspirator into the Büchner flask.See the Web Links and Related Questions to the left for more information.