3. (50 points). Consider a rigid tank containing 1 Kg of nitrogen (N$_2$) gas at a temperature T and
pressure P. The compressibility chart is
Based on this information,
3.1 The work done by the nitrogen on the tank is
a. W = 0 kJ
b. W = 14 kJ
c. W = 43 kJ
d. None of the above
3.2 Assume that nitrogen is being compressed isothermally. If 4.5 ? $P_r$ ? 6.5 and $T_r$ = 1.3 are known in
this thermodynamic problem, then the limited pressures (minimum and maximum pressures) within the
given $P_r$ range are
a. $P_1$ = 48.57 MPa
b. $P_1$ = 15.26 MPa
$P_2$ = 18.22 MPa
$P_2$ = 22.04 MPa
c. $P_1$ = 85.36 MPa
d. None of the above
$P_2$ = 96.16 MPa
3.3 The constant temperature is
a. T = 164.06 K
b. T = 286.54 K
c. T = 385.36 K
d. None of the above
3.4 Knowing the limited pressures, the work done needed to compressed nitrogen is
a. W = ?6.27 kPa
b. W = +6.27 kPa
c. W = ?12.84 kPa
d. None of the above
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