Solution:

• A refrigerant is a working fluid used in the refrigeration cycle of air conditioning systems and heat pumps where in most cases they undergo a repeated phase transition from a liquid to a gas and back again.
• It is very important that the refrigerant has a low boiling point, that is it should have the ability to turn into gas easily when it absorbs heat.
• If it has a high boiling point, the compressor will have to create too much of a vacuum in order to lower the pressure to make vaporization happen.