LITERATURE REVIEW

In 1701, Ole Christense Romer created one of the first practical thermometers. Romer’s thermometer used red wine as the temperature indicator. Romer created a temperature scale for his thermometer with O representing the temperature of a salt and ice mixture (at about 259K), 71⁄2 representing then freezing point of water (273.15K), and 60 representing the boiling water (373.15K). In 1676, Romer became the first scientist to measure the speed of light.

Daniel Gabriel Fahrenheit in 1686-1736, devoted most of his life to crating precision meteorological instrument. Fahrenheit invented the mercury thermometer in 1714, and later discovered the effect of pressure on the boiling point of liquid. Fahrenheit sought to create a practical temperature scale in which in 0 corresponded with the coldest temperature normally invented in Western Europe and 100 corresponded to the hottest temperature. Fahrenheit initially created a temperature scale in which 0 represented the temperature of a salt and ice mixture (at about 255K), 30 representing the freezing point of water (273.15K) and 90 representing the mean human body temperature (310K). Fahrenheit later adjusted his scale so that 32 representing the freezing point of water and 212 representing the boiling point of water (313.15K). The Fahrenheit temperature scale is still used today in the United States and other backward places. 1731, Rein Antoine Farchault de Reamu- created a simple temperature scale in which 0 represented the freezing point of water (273.15K) and 80 represented the boiling point (313.15K). The Reamu- temperature scale became popular in France but it was superseded by the centigrade temperature scale.

In 1742, Andes Celsius created and invented centigrade temperature scale in which 0 represented the freezing point of water (273.15K) and 100 represented the boiling point of water (373.15K). The centigrade relative temperature scale gradually became popular throughout the world. The units of the centigrade temperature scale were designated “degree centigrade” (symbol ˚C).

In 1848, William Thomson proposed a thermodynamic temperature scale which assigned 0 to thermodynamic absolute zero and used the degree centigrade scale (after Thomson’s pear title) and its unit designated degree Kelvin (symbol ˚K).

In 1859, William John Macquom Rankine proposed another thermodynamic temperature scale which also assigned 0 to thermodynamic absolute zero but used the degree Fahrenheit as its base unit. This absolute scale wsa late named the Rankine thermodynamic temperature scale and its unit designated degree Rankine (symbol ˚R).

In 1954, the tenth General conference on weights and measure selected the degree Kelvin as the metric unit of thermodynamic temperature. The degree Kelvin was named in honour of its creator Sir William Thomson Baron Kelvin of largs and lord of Scotland. The conference defined the degree Kelvin by assigning the exact value 237.16K to the triple point of water. The triple point of a substance is the thermodynamic singularity at which the gas, liquid and solid phases may coexist in thermodynamic equilibrium. A triple point is therefore a much more accurate temperature reference than either a freezing point or a boiling point.