Page 78 - DJJ20063- Thermodynamics 1

DJJ20063- Thermodynamics 1

Example 2.15

A certain perfect gas has specific heat as follows

Cp = 0.846 kJ/kg K and Cv = 0.657 kJ/kg K

Find the gas constant and the molecular weight of the gas.

Solution to Example 2.15

From equation 2.24

R = Cp - Cv

i.e. R = 0.846 – 0.657 = 0.189 kJ/kg K

or R = 189 Nm/kg K

From equation 2.18

R
M = 0
R

8314
i.e. M = = 44
189

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