Suppose 60.0 g of HBr(g) is heated reversibly from 300K to 500K at a constant volume of 50.0L and then allowed to expand isothermally and reversibly until the original pressure is reached. Knowing that CpHBr(g)= 29.1 J/Kmol, and assuming HBr is an ideal gas for these conditions, evaluate a. the change in internal energy b. the heat involved in the process c. the work

A system absorbs 1.5 kJ at 25ºC from its surroundings and later releases 1.5 kJ to its surrounding at 75ºC. Calculate the overall entropy change for the system assuming both processes are reversible .Ans: 0.7 J/K

Thermodynamics question

Liquefied natural gas (LNG) is transported in very large tankers, stored as liquid in equilibrium with its vapor at approximately atmospheric pressure. If LNG is essentially pure methane, the storage temperature then is about 111.4 K, the normal boiling point of methane. The enormous amount of cold liquid can in principle serve as a heat sink for an onboard heat engine. Energy discarded to the LNG serves for its vaporization. If the heat source is ambient air at 300 K, and if the efficiency of a heat engine is 61% of its Carnot value, estimate the vaporization rate in moles vaporized per kJ of power output. For methane, AH = 8.206 kJ.mol-¹. The vaporization rate in moles vaporized per kJ of power output is mol-kj1

Air contained in a piston-cylinder assembly undergoes the power cycle shown in the figure below. 4.5 P (bar) 1.2 0 n = i 3 1.0 v (m³/kg) Isothermal process % 4 2 Assuming ideal gas behavior for the air, evaluate the thermal efficiency of the cycle. 3.75 O

Please show the outright and legible answers/solutions. Thermodynamics  Ideal Gas Sulphur dioxide is circulated as refrigerant in a small refrigerator. SO2 gas at a pressure of 5 bar and temperature 340 K is to be cooled at a constant volume of 0.142 m3, to 293 K as part of the refrigeration cycle. Calculate (a) The heat liberated, (b) The work done by the gas on cooling, (c) The final pressure attained on cooling and(d) The change in enthalpy.Sulphur dioxide may be treated as an ideal gas. The specific heat (J/mol K) is found to vary with temperature (K) according toCP = 25.736 + 5.796 X 10-2 T – 3.8112 x 10-5 T2 + 8.612 x 10-9 T3

Thermodynamic

During methane liquefaction, about 1000 kg of methane are stored at a pressure of 10 MPa and 180 K. The plant manager is worried about the possibility of explosion of the storage tank. Determine the energy released (in kg TNT equivalent) by a sudden rupture of this storage tank and the temperature and physical state of the methane immediately after the rupture.

Air expands adiabatically in a piston-cylinder assembly from an initial state where p₁ = 100 lbf/in.², v₁ = 3.704 ft³/lb, and T₁ = 1000 °R, to a final state where p₂ = 30 lbf/in.² The process is polytropic with n = 1.4. The change in specific internal energy, in Btu/lb, can be expressed in terms of temperature change as Au = (0.171)(T2-T1). Determine the final temperature, in °R. Kinetic and potential energy effects can be neglected. T₂ = 1 °R

Steam at 0.9 MPa and dryness fraction 0.86 expands in a cylinder behind a piston isothermally and reversibly to a pressure of 0.05 MPa and temperature of 250°C. Calculate: 3.1. Change of internal energy. 3.2. Change of enthalpy per kg of steam. 3.3. Change of entropy. 3.4. The heat supplied during the process is found to be 560 kJ/kg, calculate the work done per kilogram of steam.