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Lead is a common metal that is used in electronic components. It is highly toxic and should not be ingested in large quantities, especially by children. It is a heavy metal with the atomic number 82.
The melting temperature of lead can be measured by a variety of methods. The most common is the capillary method. This technique involves heating a sample in a thin glass capillary tube until it reaches its melting point. The melting temperature of the sample is then recorded and compared to a standard reference value.
Melting temperature of a pure solid crystalline material, such as a mineral or a metal, is predicted by the Lindemann criterion (see below). The criterion states that melting is expected when the average amplitude of thermal vibrations of the crystal exceeds a threshold value.
However, the melting point of a solid may not be exactly predicted by this criterion. This is because the entropy of fusion can vary widely depending on the molecular structure of the substance, e.g. symmetry, eccentricity, chirality, flexibility, hydrogen bonding, etc.
The entropy of fusion can also be affected by the degree to which atoms in a crystalline solid are bound to each other, as is the case with ice. In order to predict the melting point of a crystalline solid, scientists have developed quantitative structure-property relationships for the determination of the temperature at which the crystalline phase melts, and the change in entropy when it melts.