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General Chemistry

Celsius Scale (Centigrade)

Definition and meaning of Celsius Scale (Centigrade) in chemistry.

Centigrade (Celsius) is a temperature scale, denoted °C, on which the freezing point of water is defined as 0 degrees and the boiling point of water as 100 degrees at standard atmospheric pressure.

In more detail

The scale was devised in 1742 by Swedish astronomer Anders Celsius, originally with the freezing and boiling points reversed; it was later inverted to its modern form. "Centigrade," meaning "hundred steps" in reference to the 100 divisions between the reference points, was the scale's common name until 1948, when the International Committee for Weights and Measures officially renamed it "Celsius" to avoid confusion with the angular unit also called "centigrade" (one-hundredth of a grad) used in some countries. Celsius degrees are the same size as kelvins, so temperature differences are numerically identical in both scales, making conversions between them simple addition or subtraction.

Key facts

Symbol°C
Conversion to KelvinK = °C + 273.15
Named AfterAnders Celsius (1742)
FieldGeneral Chemistry
Example

A laboratory water bath held at 37°C (human body temperature) corresponds to 310.15 K and 98.6°F.

Frequently asked questions

Is centigrade the same as Celsius?

Yes. They describe the identical temperature scale; "Celsius" became the official SI name in 1948, replacing the older term "centigrade."

How do you convert Celsius to Fahrenheit?

Use °F = (°C × 9/5) + 32; for example, 100°C equals 212°F.

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