How Many Freon Cycles to Lower Refrigerator Air by 12°C?

AI Thread Summary
To lower the temperature of the air in a refrigerator by 12°C, calculations must consider the amount of Freon and the energy required. The refrigerator contains 242 grams of Freon, which equates to 2 moles, and each mole requires 4.8 kcal to evaporate. The refrigerator's capacity is 120 liters, and its performance coefficient is 25%. Additionally, raising the temperature of one mole of air by 1°C requires 7 calories. The discussion emphasizes the need for initial calculations regarding the moles of air in the refrigerator to determine the number of Freon cycles needed for the desired temperature drop.
christodoulou Andrea
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please somebody help me!
Electrical refrigerator contains 242 gr.Freon(mm.121).For the evaporation of 1 mole of this freon we need 4,8kcal.the capacity of the refrigerator is 120 liters.The performance coefficient is 25%.To incease the temperature of one mole of air to 1 C degree we need 7 cal.How many times must the freon recycle to decrease the temperature of the refrigerator-air to 12 C degree.

PLEASE IS URGENT!
 
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In accordance with the rules, you have to show us some working before we can help you... If you don't know where to start, I'd recommend thinking about the values you need, before starting any calculations:

i.e. How many moles of Freon have you got?
How many moles of air are 25 litres (assuming standard air pressure & temperature)?

Personally, I think this is an engineering question.

Regards,
Sam
 
Electrical refrigerator conains 242 gr. of freon (Melecolar mass:121).For the evaporation of 1 mole of this freon are need 4,8 kcal.The capacity of the frigidaire is 120 liters and its performance coefficient is 25%.To increase the temperature of one mole of air by 1 celsius degree we need 7 cal.How many times must to the freon recycle to decrease the air of the frigidaire by 12 celsius degree.

I know tha i have 2 moles of freon.I also know the capacity and the performance coefficient but i can't continue.

Please help me!
 
christodoulou Andrea said:
please somebody help me!
Electrical refrigerator contains 242 gr.Freon(mm.121).For the evaporation of 1 mole of this freon we need 4,8kcal.the capacity of the refrigerator is 120 liters.The performance coefficient is 25%.To incease the temperature of one mole of air by 1 C degree we need 7 cal.How many times must the freon recycle to decrease the temperature of the refrigerator-air by 12 C degree.
PLEASE IS URGENT!
I know tha ihave two moles of freon but after that i can't continue
 
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