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Standard XII
Chemistry
Enthalpy
A refrigerato...
Question

A refrigerator based on ideal vapour compression cycle operates between the temperature limits of −20∘C and 40∘C. The refrigerant enters the condenser as saturated vapour and leaves as saturated liquid. The enthalpy and entropy values for saturated liquid and vapour at these temperatures are given in table below.

Thfhgsfsg(∘C)(kJ/kg)(kJ/kg)(kJ/kg K)(kJ/kg K)−20201800.070.736640802000.30.67

The COP of the refrigerator is

A
2.0
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B
2.33
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C
5.0
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D
6.0
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Solution

The correct option is B 2.33
COP=Refrigeration effectWork input

=REW=2.1m(h2−h1)

=2.10.025(200−164)=2.33

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