Talk:Melting-point apparatus

Different Apparatus

This article should probably be broken down into the four main types of apparatuses commonly used in labs to determine melting point. Under each it would be good to describe how each works and the overall procedure for using it. TheIguana (talk) 03:02, 21 October 2008 (UTC)

Fisher-Johns apparatus

The Fisher-Johns apparatus was developed by Fisher Scientific. It consists of a rheostat controlling the heating mantle and a horizontally placed thermometer. To test a materials melting point, a glass or plastic coverslip is placed over the heating mantle, a sample of the material of rice grain size or slightly smaller is then placed on the coverslip and another coverslip is placed atop. The power is then turned on and the rheostat is slowly raised while observing the sample through the eye piece. When the material begins to melt, the thermometers reading is recorded as the beginning of the melting point range. When all of the sample has melted the thermometers reading is recorded as the end of the melting point of the substance. The coverslip can then be discarded and a metal crucible with ice can be used to rapidly cool the heating mantle in preparation of the next test. TheIguana (talk) 03:02, 21 October 2008 (UTC)