A rigid, well-insulated tank is filled initially with 5.0 kg of air at a pressure of 5 bars and a temperature of 500K. A leak develops, and air slowly escapes until the pressure of the air remaining in the tank is 1 bar. Employing the ideal gas model, determine the amount of mass remaining in the tank and its temperature.

Respuesta :

Explanation:

In an isotropic process, the equation is as follows.

        [tex]\frac{T_{2}}{T_{1}} = [\frac{P_{2}}{P_{1}}]^{\frac{k - 1}{k}}[/tex]

         [tex]T_{2} = T_{1} \times [\frac{P_{2}}{P_{1}}]^{\frac{k - 1}{k}}[/tex]

As the given data is as follows.

       [tex]T_{1}[/tex] = 500 K,     m = 5 kg

       [tex]P_{1}[/tex] = 5 bar,      [tex]P_{2}[/tex] = 1 bar

Now, putting the given values into the above formula as follows.

           [tex]T_{2} = T_{1} \times [\frac{P_{2}}{P_{1}}]^{\frac{k - 1}{k}}[/tex]

           [tex]T_{2} = 500 K \times [\frac{5 bar}{1 bar}]^{\frac{1.4 - 1}{1.4}}[/tex]

                     = 315.7 K

As according to the ideal gas equation, PV = mRT

So, calculate the volume as follows.

                      V = [tex]\frac{mRT}{P}[/tex]

                          = [tex]\frac{5 kg \times 287 J/kg \times 500 K}{5 \times 10^{5}}[/tex]        (as 1 bar = 10^{5} Pa[/tex])

                          =  [tex]1.435 m^{3}[/tex]

Now, we will calculate the value of [tex]m_{2}[/tex] as follows.

                [tex]P_{2}V_{2} = m_{2}RT_{2}[/tex]

               [tex]m_{2} = \frac{P_{2}V_{2}}{RT_{2}}[/tex]

                       = [tex]\frac{1 \times 10^{5} \times 1.435 m^{3}}{315.7 K \times 287 J/kg}[/tex]

                       = 1.58 kg

Thus, we can conclude that the amount of mass remaining in the tank is 1.58 kg and its temperature is 315.7 K.