The mixture that forms when one substance dissolves in another is called a solution.

Here's a breakdown:

* Solute: The substance that dissolves (e.g., sugar).

* Solvent: The substance that does the dissolving (e.g., water).

* Solution: The homogeneous mixture that results from the solute dissolving in the solvent.

For example, when you add sugar to water and stir, the sugar dissolves, forming a sugar solution. The sugar is the solute, water is the solvent, and the resulting mixture is the solution.