Q. Match the following irreversibilities
(1) Mechanical irreversibility ------ (A) Refrigeration cycle
(2) Thermal irreversibility --------- (B) Forming of water by combination of Hydrogen and Oxygen
(3) Chemical irreversibility -------- (C) Free expansion of gas in a system
(4) External irreversibility --------- (D) Melting of ice cube under the sunlight
- Published on 21 Aug 15a. (1)-(A), (2)-(B), (3)-(C), (4)-(D)
b. (1)-(A), (2)-(D), (3)-(B), (4)-(C)
c. (1)-(C), (2)-(D), (3)-(A), (4)-(B)
d. (1)-(C), (2)-(D), (3)-(B), (4)-(A)
ANSWER: (1)-(C), (2)-(D), (3)-(B), (4)-(A)
If the irreversibility is due to a finite pressure gradient, it is called as mechanical irreversibility. Thus, free expansion of gas in a system is the example of mechanical irreversibility.
It the irreversibility is due to a finite temperature gradient, it is called as thermal irreversibility. Thus, melting of ice cube under the sunlight is the example of mechanical irreversibility.
If the irreversibility is due to a finite concentration gradient or chemical reaction in the system, it is called as chemical irreversibility. Thus, forming of water by combination of Hydrogen and Oxygen is the example of mechanical irreversibility.
In refrigeration cycle, irreversibility occurs due to temperature difference between the source and a working fluid that is refrigerant at heat supply and the temperature difference between the sink and the refrigerant at heat rejection.
