Reaumur scale

Another scale based on the thermo-metric properties of water is the Reaumur scale, in which the freezing point is set at zero degrees and the boiling point at 80 degrees. This scale has only limited application. 

There are two other temperature scales that still may be seen in old texts or journals, but are not acceptable for any current scientific work. Perhaps the rarer is the Reaumur scale (°Re). It separated the range between freezing and boiling of water into 80 units and was used in parts of Europe. The other temperature scale, the Rankine, may be referred to in old books on thermodynamics. It was named after W. J. M. Rankine, who did early research in that field. The Rankine is to Fahrenheit what Kelvin is to Celsius. In other words, just as one degree K = one degree C, one degree F = one degree R. Thus, 0 K = 0°R = -273.15°C = -459.67°F. 

Rend de Rdaumur (1683-1757), the French scientist, found that the best spirits of wine of his day expanded by 87 parts per 1000 when warmed from the temperature of melting ice to that of boiling water. Equal parts of his spirit and water gave an expansion of 67J. He therefore for simplicity chose such a mixture as expanded by 80 parts. Hence the Reaumur scale runs from o° to 8o° between those two temperatures. The choice was not... 

The Reaumur scale is not used in this country. The Fahrenheit scale is used for unscientific, medical and meteorological purposes, in England and America, The Centigrade scale is used... 

Temperature scales and the gas laws You might have noticed that the work done by Charles and Gay-Lussac preceded the development of the Kelvin scale, yet their laws require the use of temperature in kelvins. In the 1700s and early 1800s, scientists worked with several different scales. For example, a scale called the Reaumur scale was often used in France around Charles s time. On this scale—or any scale not based on absolute zero—the expression for Charles s law is more complex, requiring two constants in addition to Y and T. The Kelvin scale simplified matters, resulting in the familiar gas laws presented here. 

In 1730, before France adopted the Celsius scale, a temperature scale known as the R6aumur (°R6) scale was in use that set the freezing point and boiling points of water at 0 degrees and 80 degrees. Write an equation that relates the Reaumur scale and the Celsius scale. 

REAUMUR. A temperature scale in which 0 is the freezing point of... 

Temperature is measured by such instruments as thermometers, pyrometers, thermocouples, etc., and by scales such as centigrade (Celsius), Fahrenheit, Rankine, Reaumur, and absolute (Kelvin). 

When the temperature of pure ice is gradually raised under the ordinary atmospheric pressure, melting always commences sharply at a certain invariable temperature, which remains constant until fusion is complete. On account of the ease with which this constant temperature can be attained it has been chosen as the standard zero for the Celsius (Centigrade) and Reaumur thermometric scales. The melting-point is slightly affected by pressure, eaeh increase of one atmosphere lowering the transition temperature of ice to water by approximately 0-0075. 

Look up and then describe the following temperature scales in relation to the Kelvin scale Celsius, Fahrenheit, Rankine, and Reaumur. 

The simphcity of the relationship between the thermodynamic scale and the gas thermometer scale is due principally to the simple properties of rarefied gases, and also to the fortunate choice of mercury as thermometric substance by Celsius and Reaumur before the discovery of the gas laws. The coefficient of expansion of mercury happens to be almost exactly proportional to the coefficient of expansion of rarefied gases. All our thermodynamical relationships would have been very much more comphcated had water or alcohol, for example, or the resistance of a metal, been used for the definition of the practical scale of temperature. Their strict validity, however, would not have been affected. 

Reaumur, Rene-Antoine Ferchault de (1683-1757) French Philosopher, naturalist Rene-Antoine Reaumur was born in La Rochelle, France, in 1683. After studying mathematics in Bourges, he moved to Paris in 1703 at age 20 under the care of a relative. Like most scientists of the time, he made contributions in a number of areas, including meteorology. His work in mathematics allowed him entrance to the Academy of Sciences in 1708. Two years later, he was put in charge of compiling a description of the industrial and natural resources in France, and as a result developed a broad-based view of the sciences. It also inspired him into the annals of weather and climate with the invention of a thermometer and temperature scale. 

Unfortunately, errors in the way he fixed his points were criticized by many in the scientific community at the time, and even with modifications in the scale, instrument makers favored mercury-based thermometers. Reaumur s scale, however, lasted over a century, and in some places well into the late 20th century. 

In 1948 a General Conference on Weights and Measures was held in Paris and S vres and the suggestion was made that the term Centigrade should be replaced by Celsius this would bring the Centigrade scale into line with those of Kelvin, Fahrenheit and Reaumur. 

The encyclopedias, such as Americana, Britannica, Coilier sf Chamber sf and the German Brockhaus are generally strong on the subject of matches, especially the historical aspect, but sketchy on other branches of pyrotechnics. Nevertheless, they often make informative reading on side issues such as the history of the thermometer scales devised by Celsius, Reaumur, and Fahrenheit, the principles of optics, the phlogiston theory, etc. 

Reaumur temperature scale A temperature scale in which the melting point of ice is taken as 0°R and the boiling point of water as 80°R. It was devised by Ren6 Antoine Reaumur (1683-1757). 

Comparison of thermometers Showing the relative indications of the Fahrenheity Centigrade and Reaumur thermometer scales... 

Reaumur Temperature Scale. A little-used scale in which the temperature interval between the freezing point and boiling point of water is divided into 80 degrees. 

The Rankine temperature scale (widely used in the United States, Canada, and other countries) is the absolute scale, 0 Ra = 0 K, at the same time 1 Ra = 1°F sometimes degrees of Rankine have a symbol R, for example 0 R the same symbol is related to degrees of Reaumur however, the sign of degree should be used in this case, ie, 0°R. 

The Reaumur temperature scale is the practical scale, 0°R = 0°C, but 80°R = 100°C (currently, this scale rarely used). 

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