HVAC 125-Unit 17 Refrigerants and their
properties Question and answer 100%
correct
Define Refrigerant. - correct answers It's the fluid used in a refrigeration
system to transfer heat.
What organization has established the number designation for refrigerants? -
correct answers They were originally developed by DuPont and were
established by ASHRAE.
What are the chemical components of CFC refrigerant? - correct answers
Contains chlorine, fluorine, and carbon. They are fully halogenated
refrigerants with chlorine and fluorine replacing all hydrogen atoms of a
hydrocarbon compound.
What are the chemical components of HCFC refrigerant? - correct answers
Contains hydrogen, chlorine, fluorine, and carbon. Most bult around methane
or ethane molecules.
What are the chemical components of HFC refrigerant? - correct answers
Contains hydrogen, fluorine, carbon. Built around the ethane molecule.
What is ozone? - correct answers Ozone is a relatively unstable molecule that
has a short lifespan, it made of 3 oxygen molecules and is constantly
produced and destroyed.
Which chemical family of refrigerant has the highest ozone-depletion
potential? - correct answers CFC refrigerants.
, What is the primary safety concern when working with R-410a? - correct
answers It is poisonous and flammable.
Define the term glide when referring to zeotropic refrigerants. - correct
answers Because for zoetrope's the dew point is a higher temp than the
bubble point at any pressure so glide refers to the difference between the
bubble point and the dew point.
Explain the ASHRAE refrigerant safety designation regarding refrigerants
toxicity and flammability. - correct answers lower toxicity - requires more than
400 parts per million to be hazardous.
higher toxicity - requires less than 400 parts per million to be hazardous.
What is the difference between a compound and a zoetrope? - correct
answers Compound is a new chemical composed of multiple chemicals with
its own unique properties. Zeotropes are mixtures of two or more chemicals
that are not chemically bonded. They also can be physically separated by
distillation.
What is the difference between a zoetrope and an azeotrope? - correct
answers Azeotropes cannot be physically separated since the components
evaporate ate the same time. They also do not change their boiling point as
they boil. Still a mixture since they are not chemically bonded. Zeotropes can
be physically separated by distillation and change in percentage as they
change state.
What is the difference between a disposable refrigerant cylinder and a
refillable refrigerant cylinder? - correct answers Disposable can only be used
once and should not be refilled while refillable can be be refilled but must be
refilled by the manufacturer
properties Question and answer 100%
correct
Define Refrigerant. - correct answers It's the fluid used in a refrigeration
system to transfer heat.
What organization has established the number designation for refrigerants? -
correct answers They were originally developed by DuPont and were
established by ASHRAE.
What are the chemical components of CFC refrigerant? - correct answers
Contains chlorine, fluorine, and carbon. They are fully halogenated
refrigerants with chlorine and fluorine replacing all hydrogen atoms of a
hydrocarbon compound.
What are the chemical components of HCFC refrigerant? - correct answers
Contains hydrogen, chlorine, fluorine, and carbon. Most bult around methane
or ethane molecules.
What are the chemical components of HFC refrigerant? - correct answers
Contains hydrogen, fluorine, carbon. Built around the ethane molecule.
What is ozone? - correct answers Ozone is a relatively unstable molecule that
has a short lifespan, it made of 3 oxygen molecules and is constantly
produced and destroyed.
Which chemical family of refrigerant has the highest ozone-depletion
potential? - correct answers CFC refrigerants.
, What is the primary safety concern when working with R-410a? - correct
answers It is poisonous and flammable.
Define the term glide when referring to zeotropic refrigerants. - correct
answers Because for zoetrope's the dew point is a higher temp than the
bubble point at any pressure so glide refers to the difference between the
bubble point and the dew point.
Explain the ASHRAE refrigerant safety designation regarding refrigerants
toxicity and flammability. - correct answers lower toxicity - requires more than
400 parts per million to be hazardous.
higher toxicity - requires less than 400 parts per million to be hazardous.
What is the difference between a compound and a zoetrope? - correct
answers Compound is a new chemical composed of multiple chemicals with
its own unique properties. Zeotropes are mixtures of two or more chemicals
that are not chemically bonded. They also can be physically separated by
distillation.
What is the difference between a zoetrope and an azeotrope? - correct
answers Azeotropes cannot be physically separated since the components
evaporate ate the same time. They also do not change their boiling point as
they boil. Still a mixture since they are not chemically bonded. Zeotropes can
be physically separated by distillation and change in percentage as they
change state.
What is the difference between a disposable refrigerant cylinder and a
refillable refrigerant cylinder? - correct answers Disposable can only be used
once and should not be refilled while refillable can be be refilled but must be
refilled by the manufacturer
