CoachA solid dissolves in water when, mixed into the water and stirred, it disappears from sight and leaves the liquid clear, that is, see-through. Sugar and salt dissolve in water. The clear liquid we obtain is called a solution: sugar water is a solution of sugar, salty water a solution of salt.
Examples
Example 2.6 (A sugar cube in a glass of water)
A sugar cube is placed at the bottom of a glass of still water. Its corners soften, it grows smaller, and wavy streaks rise from it through the water. If we stir, it is gone within a minute. If we do not stir, it still disappears, only much more slowly.