1. Temperature.
For gaseous solutes, increasing temperature leads to reduced solubility due to expansion of gas. However, for other solutes temperature affects solubility according to the heat of solution. If the heat of solution of the solute in the solvent is negative (i.e. heat is produced during dissolution; exothermic process) then solubility decreases when temperature is raised. On the other hand, if the dissolution process is endothermic (i.e. heat is absorbed during dissolution) then solubility increases when temperature is raised.
2. Solution pH.
Solution pH affects the extent of ionization. Compounds in ionized forms have higher solubility in water when compared to the nonionized forms. Therefore, weakly acidic compounds have higher solubility at higher pH values and weakly basic compounds have higher solubility at lower pH values.
3. Salting out.
Presence of an electrolyte solute in solution creates competition on solvent (water) molecules which leads to reduced solubility. For example, presence of sodium chloride reduces solubility of carbon dioxide in water.
4. Pressure.
This is especially important if the solute is in the gaseous state. For example, carbon dioxide has higher solubility in water if pressure above the solution increases.
5. Nature of the solvent.
Generally, the closer the dielectric constant (dipole moment) between the solute and the solvent the higher the solubility.
6. Chemical reaction.
The solute can react with the solvent to produce a product. For example, ammonia reacts with water to produce ammonium ions. This leads to increase in solubility compared to what is expected if there was no reaction..
Related posts:
What is solubility and how is it measured?
Solution pH and solubility of weakly acidic compounds.
For gaseous solutes, increasing temperature leads to reduced solubility due to expansion of gas. However, for other solutes temperature affects solubility according to the heat of solution. If the heat of solution of the solute in the solvent is negative (i.e. heat is produced during dissolution; exothermic process) then solubility decreases when temperature is raised. On the other hand, if the dissolution process is endothermic (i.e. heat is absorbed during dissolution) then solubility increases when temperature is raised.
2. Solution pH.
Solution pH affects the extent of ionization. Compounds in ionized forms have higher solubility in water when compared to the nonionized forms. Therefore, weakly acidic compounds have higher solubility at higher pH values and weakly basic compounds have higher solubility at lower pH values.
3. Salting out.
Presence of an electrolyte solute in solution creates competition on solvent (water) molecules which leads to reduced solubility. For example, presence of sodium chloride reduces solubility of carbon dioxide in water.
4. Pressure.
This is especially important if the solute is in the gaseous state. For example, carbon dioxide has higher solubility in water if pressure above the solution increases.
5. Nature of the solvent.
Generally, the closer the dielectric constant (dipole moment) between the solute and the solvent the higher the solubility.
6. Chemical reaction.
The solute can react with the solvent to produce a product. For example, ammonia reacts with water to produce ammonium ions. This leads to increase in solubility compared to what is expected if there was no reaction..
Related posts:
What is solubility and how is it measured?
Solution pH and solubility of weakly acidic compounds.
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