concentration
As more solute dissolves in a solvent, the solubility of the solute in the solvent increases. This leads to an increase in the concentration of the solution. The solution becomes more concentrated as more solute particles are dispersed in the solvent.
A solute generally dissolves more rapidly the warmer the solvent. Also, any mixing or moving of the solute, and also if the solute is broken up (increases surface area) both speed up dissolving.
solute dissolves more rapidly in hot water
the boiling point of the solution for one.
As the particle size gets smaller, the surface area increases, and as the surface area increases, the ease with which water can hydrate the particles increases. When it is easier for water to hydrate the molecules, this increases the speed at which the solute dissolves.
The solvent dissolves the solute. (The solute dissolves in the solvent.)
The solvent dissolves the solute. (The solute dissolves in the solvent.)
Shaking affects the rate at which a solute dissolves because it increases the molecular activity of the solute within the solvent. When the molecular activity is increased, the rate of dissolving is also increased.
Not necessarily just changing the surface area causes the rate to change. Changing the ratio of surface area volume changes the rate at which a solute dissolves in a solvent. If the surface area is larger and the volume of a solute is smaller or the same, then the rate at which the solute dissolves in a solvent increases. If the surface area is smaller and the volume of the solute is larger or the same, then the rate at which the solute dissolves in a solvent decreases.
Agitation increases the rate of dissolving by enhancing the mixing of solvent and solute particles, resulting in more frequent collisions and increased surface area contact. This helps break down the solute particles more quickly and allows them to dissolve faster.
The substance that dissolves is called the "solute" and the substance that the solute dissolves in is called the "solvent".
Reducing particle size results in an increase in surface area. The increase in surface area allows more solvent (water) molecules to interact with the substance, and this increases the rate at which that substance dissolves.