A) Celsius Scale
Celsius Scale is based on the freezing and boiling points of pure water.
The freezing point of pure water is zero degrees Celsius (0 0C), while the boiling point of pure water is 100 degrees Celsius (100°0C).
Lower Fixed Point (00C)The lower fixed point is the temperature of pure melting ice. It is also known as ice point which is 0°C.
The upper fixed point is the temperature of the pure boiling water which is 100o°C.
B) Kelvin Scale
Although there is no upper fixed limit for temperature, there is a lower limit that is -273oC. So the lowest possible temperature is known as absolute zero (0K).
The degrees on the absolute scale are called Kelvins. The size of each degree in Kelvins scale is exactly the same as the size of Celsius scale.
1oC = 1 K
The Celsius temperature is converted to Kelvin temperature by adding 273.
T (K) = temperature in oC + 273
