Baumé scale
Encyclopedia
The Baumé scale is a pair of hydrometer
scales developed by French pharmacist Antoine Baumé
in 1768 to measure density
of various liquids. The unit of the Baumé scale has been notated variously as degrees Baumé, B°, Bé° and simply Baumé (the accent is not always present). One scale measures the density of liquids heavier than water and the other, liquids lighter than water. The Baumé of distilled water
would be 0.
) and degrees Baumé is:
An older version of the scale for liquids heavier than water, at a reference temperature of 15.5 °C (59.9 °F), uses 144.32 rather than 145.
scale is a result of adapting to the subsequent errors from the Baumé scale. The Baumé scale is related to the Balling, Brix
, Plato and 'specific gravity
times 1000' scales.
around the time of World War II
the Baumé scale was generally used in industrial chemistry and pharmacology
for the measurement of density of liquids. Today the Baumé scale is still used in various industries such as brewing, sugar beet processing, ophthalmics, starch
industry, and winemaking.
Hydrometer
A hydrometer is an instrument used to measure the specific gravity of liquids; that is, the ratio of the density of the liquid to the density of water....
scales developed by French pharmacist Antoine Baumé
Antoine Baumé
Antoine Baumé was a French chemist.He was born at Senlis. He was apprenticed to the chemist Claude Joseph Geoffroy, and in 1752 was admitted a member of the École de Pharmacie, where in the same year he was appointed professor of chemistry...
in 1768 to measure density
Density
The mass density or density of a material is defined as its mass per unit volume. The symbol most often used for density is ρ . In some cases , density is also defined as its weight per unit volume; although, this quantity is more properly called specific weight...
of various liquids. The unit of the Baumé scale has been notated variously as degrees Baumé, B°, Bé° and simply Baumé (the accent is not always present). One scale measures the density of liquids heavier than water and the other, liquids lighter than water. The Baumé of distilled water
Distilled water
Distilled water is water that has many of its impurities removed through distillation. Distillation involves boiling the water and then condensing the steam into a clean container.-History:...
would be 0.
Conversions
At 20 °C (68 °F), the relationship between specific gravity (s.g.) (relative densityRelative density
Relative density, or specific gravity, is the ratio of the density of a substance to the density of a given reference material. Specific gravity usually means relative density with respect to water...
) and degrees Baumé is:
- For liquids more dense than water: s.g. = 145 ÷ (145 - degrees Baumé);
- For liquids less dense than water: s.g. = 140 ÷ (degrees Baumé + 130).
An older version of the scale for liquids heavier than water, at a reference temperature of 15.5 °C (59.9 °F), uses 144.32 rather than 145.
Definitions
Baumé degrees (heavy) originally represented the percent by mass of sodium chloride in water at 60 °F (15.6 °C). Baumé degrees (light) was calibrated with 0°Bé (light) being the density of 10% NaCl in water by mass and 10°Bé (light) set to the density of water.Other scales
Because of vague instructions or errors in translation a large margin of error was introduced when the scale was adopted. The API gravityAPI gravity
The American Petroleum Institute gravity, or API gravity, is a measure of how heavy or light a petroleum liquid is compared to water. If its API gravity is greater than 10, it is lighter and floats on water; if less than 10, it is heavier and sinks...
scale is a result of adapting to the subsequent errors from the Baumé scale. The Baumé scale is related to the Balling, Brix
Brix
Degrees Brix is the sugar content of an aqueous solution.One degree Brix is 1 gram of sucrose in 100 grams of solution and represents the strength of the solution as percentage by weight . If the solution contains dissolved solids other than pure sucrose, then the °Bx is only approximate the...
, Plato and 'specific gravity
Gravity (beer)
Gravity, in the context of fermenting alcoholic beverages, refers to the specific gravity, or relative density compared to water, of the wort or must at various stages in the fermentation. The concept is used in brewing and wine making industry...
times 1000' scales.
Use
Before standardisation on specific gravitySpecific gravity
Specific gravity is the ratio of the density of a substance to the density of a reference substance. Apparent specific gravity is the ratio of the weight of a volume of the substance to the weight of an equal volume of the reference substance. The reference substance is nearly always water for...
around the time of World War II
World War II
World War II, or the Second World War , was a global conflict lasting from 1939 to 1945, involving most of the world's nations—including all of the great powers—eventually forming two opposing military alliances: the Allies and the Axis...
the Baumé scale was generally used in industrial chemistry and pharmacology
Pharmacology
Pharmacology is the branch of medicine and biology concerned with the study of drug action. More specifically, it is the study of the interactions that occur between a living organism and chemicals that affect normal or abnormal biochemical function...
for the measurement of density of liquids. Today the Baumé scale is still used in various industries such as brewing, sugar beet processing, ophthalmics, starch
Starch
Starch or amylum is a carbohydrate consisting of a large number of glucose units joined together by glycosidic bonds. This polysaccharide is produced by all green plants as an energy store...
industry, and winemaking.