Answer in Molecular Physics | Thermodynamics for MKHUSELI #144737
February 21st, 2023
The volume of air at a pressure of 5 bar and at a temperature of 470o C is 0.5 m3. Calculate the mass of the air, and the gas constant. The universal gas constant is 8.315kJ/kg K.
“PV= nRT”
also “PV= frac{mass}{m.mass}cdot RT”
molar mass(air) = 0.029kg/mol
P= pressure= 5 Bar = 500000N/m2
V= volume = 0.5m3
T= Temperature= 4700 C = 470 + 273= 743K
R= universal gas constant= 8.315kJ/kg
“500000times0.5 = ntimes 8.315times743”
“n” = “frac{500000times0.5}{8.315times743}” mol
= 40.466mol
“n=frac{mass}{molar. mass}”
40.466“=frac{mass}{0.029}”
mass “approx” 1.174Kg
Gas constant of air
“Gas constant = frac{universal hspace{0.05cm}gashspace{0.05cm}constant}{m.mass}”
“gashspace{0.05cm}constant = frac{8.315}{0.029}”
“gas constant = 287J/Kgcdot K”
