Certain substances absorb moisture from the atmosphere when they are exposed to it but not enough to form solution. Such substances are called hygroscopic substances.
CH 3 WATER
The conical pillar which grows downwards from the roof is called Stalactite.
Dehydrating agents are substances that can remove even the chemically combined water molecules from compounds .
Drying agents are substances that can readily absorb moisture from other substances without chemically reacting with them.
A phenomenon where a compound loses its water of crystallisation on exposure to dry air is called Efflorescence.
On heating , crystals of sodium chloride produce a crackling sound, called decrepitation.
The crystals of some salts contain water of crystallisation. This water gives the crystals their shape, such salts are known as Hydrated salts.
The fixed amount of water that is associated with some compounds which is an integral part of thoer crystalline structurenis called Water of crystallisation.
The process of inducing crystallisation by adding a crystal of a pure substance into its saturated solution is called Seeding.
Crystallisation is a process by which crystals of a substance are obtained by cooling a hot saturated solution.