Absolute Zero Temperature
Theoretically, there is no limit for maximum temperature but there is a sharp point for minimum temperature that no body can have the temperature lower than this minimum value of temperature which is known as absolute zero temperature.
Absolute Zero Temperature From p-T Graph
The variation of pressure(P) with temperature(T) can be represent by following graph.
The graph is extrapolated, it meets the temperature axis at -273.15 ⁰C and in kelvin(0- K). This is because at this temperature, pressure and volume of the gas become zero.
Hence, the lowest temperature of – 273.15 ⁰C at which gas is supposed to have zero volume or zero pressure and at which entire molecular motion stopes, is called absolute zero of temperature.
The plot for pressure versus temperature and extrapolation of lines for low density gases (A, B and C) indicates the same absolute zero temperature.
The absolute zero temperature is regarded as 0 kelvin or – 273.15 ⁰C. This implies
273.15 K = 0 ⁰C