Generally the filled height should not exceed 3 mm.Īlong with proper sample preparation, the settings on the instrument are as well essential for the exact determination of the melting point. Step 4: The correct filling height can be checked with the engraved ruler on the capillary filling tool. The 'bouncing effect' causes tight packing of the substance and avoids the inclusion of air pockets. This action packs the sample tightly down into the bottom of the capillary. Step 3: The small amount of sample at the top of the capillaries is then moved down the capillary by releasing the grip and gently bouncing the capillaries on the table several times. Collecting a small sample portion from a mortar is easily done with the assistance of the tool. The capillary filling tool perfectly assists the filling as the empty capillaries are securely held in a peg-like grip. Step 2: Several capillaries are prepared simultaneously for measurement with a METTLER TOLEDO instrument. Then a small portion of sample is finely ground in a mortar. Step 1: First, the sample needs to be dried in a desiccator. Sample preparation process using METTLER TOLEDO melting point tools: Compared to other physical values the change in light transmission can easily be determined and can therefore be used for melting point detection. Last but not least, the optical properties birefringence reflection and light transmission change. Amongst these are the thermodynamic values, specific heat capacity, enthalpy, and rheological properties such as volume or viscosity. The melting temperature of a crystalline solid is thus an indicator for the stability of its lattice.Īt the melting point not only the aggregate state changes quite a lot of other physical characteristics also change significantly. The more energy is needed, the higher the melting point. The stronger the forces of attraction between the particles, the more energy is needed to overcome them. The crystalline structure is destroyed and the solid material melts. When the solid crystalline material is heated, the particles become more energetic and start to move more strongly, until finally the forces of attraction between them are no longer strong enough to hold them together. The particles within the lattice are held together by lattice forces.
During the phase transition, the two physical phases of the material exist side-by-side.Ĭrystalline materials consist of fine particles that for a regular, 3-dimensional arrangement – a crystalline lattice. During the melting process, all of the energy added to the substance is consumed as heat of fusion, and the temperature remains constant (see diagram below). This phenomenon occurs when the substance is heated. It is the temperature at which the solid phase changes to the liquid phase.
This effect is used to identify the degree of impurity of the substance.Melting point is a characteristic property of solid crystalline substance. As a result, most substances that are examined with a melting point meter have a melting interval. Even impurities during the manufacture of chemicals cause this melting point to expand to a melting interval. Due to impurities, such as impurities or dopants, most substances have a melting interval (beginning of the melt to completion of the melt) of a few degrees Celsius. A well-defined melting point is only given for 100 percent pure substances. The purity of substances can also be qualitatively measured via melting point. The determination of the melting point is of great importance in the identity test, since many substances can be determined by their melting point. Includes protective cover and 100 capillaries.With RS-232 interface for printer CBM910.Monitoring of the illuminated sample via lens.The display provides a wellarranged readout of all important measuring data. Thanks to the preheating rate and the integrated fan cooling, fast measurements are possible in any temperature range. Due to the triple capillary intake, it is possible to analyse three samples within one measurement run. The Melting Point Apparatus for semi-automatic measurement M3000 provides fast and easy examination of powdery substances with a melting point up to 360 ☌.