Unit 25 - Chapter 114 Flashcards
What group does r-22 or freon-22 belong to?
A1
Which of the following characteristics is common in all group b refrigerants?
High toxicity
The ideal commercial refrigerant should
Be environmentally friendly
Ammonia refrigerants
Are well suited for industrial and commercial refrigeration
What’s the refrigerants that is nonflammable, odourless, nontoxic, has a boiling point of -40.6, and doesn’t have a corrosive effect on metals?
Freon 22
The refrigerant r-11 belong to the group
A1
Which of the following is a thermodynamic property of heat?
- entropy
- Enthalpy
- density
- volume
The property which has to be known for the calculation of the size of control valves and piping is
Density
The refrigerating effect of a refrigerant is
Equal to its latent heat of evaporation
The standard refrigeration cycle is used to compare refrigerants and machines operating under comparable conditions, which are
30 degrees condensing and -15 evaporating
The latent heat of fusion of ice is
335 kJ per 1 kg
The ability if a refrigerant to be dissolved into oil is called
Miscibility
Which is not a physical property of refrigerants?
Density
Ammonia is the only commonly use refrigerant which has the physical property of
Flammability
Molecular mass is a dependent factor on what physical property?
Leakage tendency
