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Temperature diagram

Temperature is a measure of the average kinetic energy of translation of the gas molecules.



Temperature is the quantity that tells how warm or cold an object is with respect to some standard. It is a measure of the average kinetic energy of the molecules or atoms in an object. The temperature of matter is expressed by a number that corresponds to the degree of hotness on a chosen scale: Celsius, Fahrenheit, or kelvins.

In most laboratory work, temperature is expressed in degrees Celsius, named after the 18th century Swedish astronomer Anders Celsius. On the Celsius scale, zero is assigned to the temperature at which water freezes, and 100 is given to the boiling point of water. The Celsius scale is the same as the centigrade scale.

The United States uses the Fahrenheit scale to express temperatures. In this scale, the value 32 is assigned to the freezing point of water and 212 to its boiling point. Conversion to the Fahrenheit scale from Celsius is through the formula: degrees Celsius = 5/9(degrees Fahrenheit-32).

Scientists also used the Kelvin scale, named after the British scientist Lord Kelvin. On this scale, zero is assigned to absolute zero-the lowest possible temperature. At absolute zero, a substance has no kinetic energy. Absolute zero corresponds to -273° on the Celsius scale.