Drying agent

Most common drying agents are anhydrous inorganic salts. These solids are insoluble in organic solvents and remove the water by forming hydrates.
  • The drying agent is added to the solution to be dried and left for about 10 min. When dry, solutions usually are clear, not cloudy.

Hydrated inorganic salts are usually unstable when heated, hence this process should be carried out at room temperature. The hydrates must be removed by filtration before a dried solution is heated.