Chemical Engineering Thermodynamics - Study Mode
[#1] Joule-Thomson effect i.e., a throttling process is a constant __________ process.
Correct Answer
(D) Enthalpy
Explanation
Solution: Joule – thomson throttling process is an iso-enthalpic process since pressure change is done at constant enthalpy that means a pressure change will occur but a corresponding internal energy change also occurs and enthalpy remains constant. Since $$H = U + PV$$
[#2] Throttling (Joule-Thomson effect) process is a constant __________ process.
Correct Answer
(A) Enthalpy
Explanation
Solution: Joule – thomson throttling process is an iso-enthalpic process since pressure change is done at constant enthalpy that means a pressure change will occur but a corresponding internal energy change also occurs and enthalpy remains constant. Since $$H = U + PV$$
[#3] A refrigeration cycle is a reversed heat engine. Which of the following has the maximum value of the co-efficient of performance (COP) for a given refrigeration effect?
Correct Answer
(D) Carnot refrigeration cycle
Explanation
Solution: Carnot refrigeration cycle has maximum COP since carnot is an ideal cycle consisting of reversiable changes at each and every step and hence no losses.
[#4] A nozzle is a device, which
Correct Answer
(A) Increases kinetic energy and decreases pressure
Explanation
Solution: Usually a nozzle is an converging duct so along the flow the area decreases so, by continuity we can say velocity increases when velocity increases (kinetic energy increases) we can say pressure decreases by bernoulli equation.
[#5] The first law of thermodynamics is a statement of conservation of
Correct Answer
(C) Energy
Explanation
Solution: The first law of thermodynamics is an conservation of energy which states that energy cant be destroyed energy can be converted from one from to other but energy is not destroyed during the process and the energy of an isolated system always remans constant. $$delta Q = dU + delta W$$