Melting Point
| Formula / Notation | T_m: solid ⇌ liquid at fixed P; ΔT_f = K_f × m (freezing point depression) |
|---|---|
| Also Known As | Melting temperature, fusion point, liquefaction temperature, T_m |
What is Melting Point?
The temperature at which a solid changes to a liquid at a given pressure. Pure substances have sharp, characteristic melting points. Impurities lower and broaden the melting point (melting point depression). Melting points are used to identify and assess purity of solid compounds.
Formula & Notation
Other Names / Synonyms: Melting temperature, fusion point, liquefaction temperature, T_m
Properties & Characteristics
Uses & Applications
Safety Information
Always consult the SDS/MSDS before handling any chemical. This information is for educational purposes only.
Key Facts
Frequently Asked Questions
The temperature at which a solid changes to a liquid at a given pressure. Pure substances have sharp, characteristic melting points. Impurities lower and broaden the melting point (melting point depression). Melting points are used to identify and assess purity of solid compounds.
Melting point determination is a standard characterisation technique in organic chemistry (mixed melting point test for identity). Industrial melting points are important for: materials selection, processing temperatures, phase change materials, food processing (chocolate tempering), metals casting,…
Working above the melting point of a substance requires appropriate high-temperature PPE (heat-resistant gloves, face shield). Molten metals and salts at their melting points cause severe burns. Many organic solids release flammable or toxic vapours above their melting points.
The formula or notation for Melting Point is: T_m: solid ⇌ liquid at fixed P; ΔT_f = K_f × m (freezing point depression)