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The pressure is expressed in Pascal: IP = N/m .
b) The molecular mass is the ratio of the molecule mass to
I2
1/12 part of C atom's mass:
1  27
1 a. u. m  m 12  . 1 6606 10 kg (1.3.2)
12 C

The mole is the quantity of a substance, which consists of such number
12
of molecules that equals to the number of atoms in 12 grams of the C
isotope.

Avogadro's law states that one mole of different substances consists of
the same number of molecules
1
23
N = 6,022 10 mole- .
A

The molar mass M is the mass of one mole and it equals to the ratio of
the substance mass m to the number of moles v, which it consist of:

m
M  (1.3.3)
v
The molar mass is expressed in kg/mole.
c) The temperature is the physical value, which is proportional to the
internal energy of body. There exist different scales to measure the

temperature.
Celsius is a scale and unit of measurement for temperature. It is named
after the Swedish astronomer Anders Celsius (1701–1744), who

developed a similar temperature scale. The degree Celsius (°C) can refer
to a specific temperature on the Celsius scale as well as a unit to indicate a
temperature interval, a difference between two temperatures . 0 °C
was defined as the freezing point of water and 100 °C was defined as the

boiling point of water, both at a pressure of one standard atmosphere with
mercury being the working material. Although these defining correlations
are commonly taught in schools today, by international agreement the unit

"degree Celsius" and the Celsius scale are currently defined by two
different temperatures: absolute zero, and the triple point of specially
purified water. This definition also precisely relates the Celsius scale to
the Kelvin scale, which determines the SI base unit of thermodynamic

temperature with symbol K. Absolute zero, the lowest temperature
possible at which matter reaches minimum entropy, is defined as being
precisely 0 K and −273.15 °C. The temperature of the triple point of water

is defined as precisely 273.16 K and 0.01 °C.

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