Give a long answer to the question given below.

In what way hygroscopic substances differ from deliquescent substances. 
 
Hygroscopic substances:
 
Substance when exposed to atmospheric air, they absorb moisture their physical state. These substances are known as and used as . They may be solids or liquids. 

For example,  silica gel \(SiO_2\) and .

Deliquescent substances:
 
Deliquescent substances when exposed to the atmospheric air at ordinary temperatures, absorb enough water and get  dissolved. Such property is called . When deliquescent substances are exposed to air, their physical state . They are solids.
For example, ferric chloride and .