It is important to heat the sample slowly using this method so that a thermal equilibrium can be established. Sample Preparation Take a special glass capillary that fits the melting point apparatus in use. The solid may be approaching its melting point if the solid is seen pulling away from the walls of the tube to form a cone of solid Figure 6.
Insert the thermometer through a hole in a cork, and clamp the cork to the ring stand as shown. If your institution is subscribed to the Organic Chemistry II.
Dip the open end of the capillary into a sample of benzoic acid Gently tap the glass capillary on a hard surface, like a table, so that the benzoic acid moves down to the very bottom of the glass capillary 2.
Note the temperature t1 when the substance starts melting. This method involves placing the sample in a capillary tube and running an experiment that will heat the sample until it reaches melting point.
The rate of heating is often experimental and should be adjusted by careful monitoring of the thermometer on the apparatus. You should now understand melting point, how it's measured, and its applications.
Fill the capillary tube with the substance. Set the temperature by using the dial and turn on the apparatus by flipping the switch.