Why anhydrous salt is less soluble in water than hydrous salt

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Homework Statement

I just wanted to ask why anhydrous salt is less soluble in water than hydrous salt especially in case of glauber's salt

Thank you very much!

 

[chemisttree]

Why do you think the anhydrous form is less soluble?

 

[Blueshift5]

I can explain why anhydrous salt is less soluble in water than hydrous salt. Anhydrous salt is a type of salt that does not contain any water molecules in its crystal structure, while hydrous salt contains water molecules in its crystal structure. This difference in structure affects the solubility of the salt in water.

When anhydrous salt is added to water, it does not have any water molecules to interact with the water molecules. This means that the anhydrous salt particles are not able to break apart and dissolve in the water as easily as hydrous salt. On the other hand, hydrous salt has water molecules in its crystal structure which can easily interact with the water molecules in the solution, allowing the salt particles to break apart and dissolve more easily.

Additionally, the presence of water molecules in hydrous salt can also create a hydration shell around the salt particles, making them more stable and less likely to precipitate out of the solution. This further increases the solubility of hydrous salt compared to anhydrous salt.

In the case of Glauber's salt (sodium sulfate decahydrate), the presence of 10 water molecules in its crystal structure makes it more soluble in water compared to anhydrous sodium sulfate. This is because the water molecules in Glauber's salt can interact with the water molecules in the solution, increasing its solubility.

In summary, the presence of water molecules in the crystal structure of hydrous salt allows for easier interaction with water molecules in the solution, making it more soluble than anhydrous salt.