Functionality of the melting point apparatus

It is important to understand how the melting point machine actually works. This can be broken apart to identify the key functional parts of the machine that allows it to simultaneously hold and heat the sample steadily whilst informing the user of the current temperature within the machine.

The 4 key parts of the machine are the heating chamber, the capillary tube, the magnifying glass, and the temperature display.

Heating Chamber The tube is inserted in a heating chamber or an oil bath, where the temperature can be raised through a control pane. Old instruments also present a mercury thermometer, while more modern ones show the temperature on a display. These modern machines also allow setting a heat gradient, which is how much the temperature should rise in a determined time period (units/minute).

Capillary tube The capillary tube acts as the container of the sample. The capillaries are made of glass, as it’s vital that the operator can see through them and the changes of phase in the sample. Furthermore, glass has good resistance to heat.

Temperature screen display It is imperative to have a way to measure the temperature as well as monitor it. In the machines, a useful part is a screen where it displays the current temperature inside the heating chamber at any given time so we can determine the exact temperature range at which the solid melts.

Magnifying lens Lastly, another important part of the machine is the magnifying lens. This acts as either a visible window or an eyepiece to look through so that you get a clear zoomed-in view of the melting process. This is important as the tube is very thin and there will only be a small amount of sample inside.