Question

Heat is transferred directly from a heat reservoir at 200 C to another heat reservoir at 5C. If the amount of heat transferred is 100kJ, what is the total entropy change as a result of this process? Draw a schematic to represent the heat exchange

Answer 1

Answer:

ΔS=0.148  KJ/K

Explanation:

Given that

Q = 100 KJ

T₁=200°C

T₁=200+273 = 437 K

T₂=5°C

T₂=5 + 273 = 278 K

Reservoir 1 is rejecting heat that is why it taken as negative while the reservoir 2 is gaining the heat that is why it is taken as positive.

So the total change in entropy given as

ΔS=  - Q/T₁ + Q/T₂

ΔS=  - 100/473 + 100/278  KJ/K

ΔS=0.148  KJ/K