1.2 Temperature scale  The range between the fixed points is divided into a number of equal divisions called degrees. Temperature scale  It is obtained by choosing two temperatures called fixed points. What is temperature scale?

1.2 Temperature scale  Celsius scale – the most commonly used temperature scale Celsius scale melting ice 0  C 1. The lower fixed point or ice point = 0  C  The fixed points of the Celsius scale:

1.2 Temperature scale  Each division is called a degree Celsius, written as  C.  The temperature range between the lower and upper fixed points is divided into 100 equal divisions. 2. The upper fixed point or steam point = 100  C boiling water 100  C

1.2 Temperature scale  Scientists often use the Kelvin scale for measuring temperatures. Kelvin scale  Kelvin scale is also called the absolute temperature scale.  Absolute zero (0 K) – lowest possible temperature of matter  A kelvin has the same size as a degree Celsius.  Unit: kelvin, K

1.2 Temperature scale melting ice 273 K boiling water 373 K Kelvin temperature = Celsius temperature + 273

1.2 Temperature scale That’s the end of Section 1.2 Check Point Key Ideas Previous Page Section 1.3 Exit