Réaumur (°Ré) - Unit Information & Conversion
What is a Réaumur?
Definition
The Réaumur scale (°Ré, °Re, °R) is a temperature scale where the freezing point of water is 0 degrees and the boiling point is 80 degrees.
History
Developed by René Antoine Ferchault de Réaumur in 1730, it was based on the expansion of alcohol. He marked the freezing point as 0 and the boiling point of the alcohol solution as 80. It gained popularity in parts of Europe, particularly France and Germany, but has largely been replaced by Celsius.
Common Uses
- Historical Context: Found in old scientific literature and historical documents.
- Specific Industries: Occasionally used in some specific contexts, such as cheesemaking in Italy (for Parmigiano-Reggiano) or for measuring sugar syrup temperature in some Dutch cooking.
Unit FAQs
What are the freezing and boiling points of water in Réaumur?
Water freezes at 0 °Ré and boils at 80 °Ré.
How does Réaumur relate to Celsius?
The Réaumur degree is larger than the Celsius degree. The formula is °Ré = °C × 4/5.
Is the Réaumur scale still commonly used?
No, it is rarely used today, having been largely superseded by the Celsius scale.
Réaumur Conversion Formulas
To Celsius:
To Fahrenheit:
To Kelvin:
To Rankine:
To Rømer:
To Newton:
To Delisle:
Convert Réaumur
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