A. Reversible isothermal
B. Irreversible isothermal
C. Reversible adiabatic
D. None of these
Related Mcqs:
- Steam undergoes isentropic expansion in a turbine from 5000 kPa and 400°C (entropy = 6.65 kJ/kg K) to 150 kPa) (entropy of saturated liquid = 1.4336 kJ/kg. K, entropy of saturated vapour = 7.2234 kJ/kg. K) The exit condition of steam is_______________?
A. Superheated vapour
B. Partially condensed vapour with quality of 0.9
C. Saturated vapour
D. Partially condensed vapour with quality of 0.1 - The expression for entropy change, ΔS = n Cp . ln (T2/T1), is valid for the ______________ of a substance?
A. Simultaneous pressure & temperature change
B. Heating
C. Cooling
D. Both B. and C - High pressure steam is expanded adiabatically and reversibly through a well insulated turbine, which produces some shaft work. If the enthalpy change and entropy change across the turbine are represented by ΔH and ΔS respectively for this process ?
A. Δ H = 0 and ΔS = 0
B. Δ H ≠ 0 and ΔS = 0
C. Δ H ≠ 0 and ΔS ≠ 0
D. Δ H = 0 and ΔS ≠ 0 - Chemical potential (an intensive property) of a substance is a force that drives the chemical system to equilibrium and is equal to its partial molar properties. The ratio of chemical potential to free energy of a pure substance at constant temperature and pressure is________________?
A. 0
B. 1
C. ∞
D. None of these - During a reversible isothermal expansion of an ideal gas, the entropy change is_________________?
A. +ve
B. 0
C. -ve
D. ∞ - During a reversible isothermal expansion of an ideal gas, the entropy change is___________________?
A. +ve
B. 0
C. -ve
D. ∞ - “At the absolute zero temperature, the entropy of every perfectly crystalline substance becomes zero”. This follows from the __________________?
A. Third law of thermodynamics
B. Second law of thermodynamics
C. Nernst heat theorem
D. Maxwell’s relations - Specific _____________ does not change during phase change at constant temperature and pressure?
A. Entropy
B. Gibbs energy
C. Internal energy
D. Enthalpy - _____________________ remains constant during the adiabatic cooling of moist air?
A. Wet bulb temperature
B. Dry bulb temperature
C. Relative humidity
D. Specific humidity - A solid metallic block weighing 5 kg has an initial temperature of 500°C. 40 kg of water initially at 25°C is contained in a perfectly insulated tank. The metallic block is brought into contact with water. Both of them come to equilibrium. Specific heat of block material is 0.4 kJ.kg-1. K-1. Ignoring the effect of expansion and contraction and also the heat capacity to tank, the total entropy change in kJ.kg-1, K-1 is_________________?
A. -1.87
B. 0
C. 1.26
D. 3.91