A closed insulted tank has two compartments A and B, both filled with helium (assumed to be ideal gas). The partition separating the two compartments is fixed and is a perfect heat insulator (Figure 1

Question

A closed insulted tank has two compartments A and B, both filled with helium (assumed to be ideal gas). The partition separating the two compartments is fixed and is a perfect heat insulator (Figure 1). If the old partition is replaced by a new partition which can slide and conduct heat but does NOT allow the gas to leak across(Figure 2), the final pressure of gas (bar) after the system attains equilibrium.

TestHub · Accepted Answer

W = 0 , q = 0 , Δ U = 0 n A ​ C V ​ ( T − 400 ) + n B ​ C V ​ ( T − 300 ) n A ​ n B ​ n B ​ n A ​ ​ ( 4 45 ​ ) ( T − 400 ) + ( T − 300 ) 4 49 ​ T 4 49 ​ T T T A ​ P A ​ V A ​ ​ + T B ​ P B ​ V B ​ ​ P F ​ P F ​ P F ​ P F ​ ​ = 0 = R T A ​ P A ​ V A ​ ​ = R T B ​ P B ​ V B ​ ​ = 5 × 3 × 4 3 ​ = 4 45 ​ = 0 = 300 + 4 45 ​ × 400 = 300 + 4500 = 4800 = 49 4800 × 4 ​ = T F ​ P F ​ ( V A ​ + V B ​ ) ​ = ( 4 ) ( 400 5 × 1 ​ + 300 1 × 3 ​ ) × 49 4800 × 4 ​ ​ = 49 ( 4 5 ​ + 1 ) × ( 48 ) ​ = 4 9 ​ × 49 48 ​ = 49 12 × 9 ​ = 2.20 bar ​

Chemistry - Thermodynamics - 1 Question with Solution | TestHub

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