When a solid is dissolved in water, the mixture is called a solution.

Here's why:

* Solution: A solution is a homogeneous mixture where one substance (the solute) is dissolved evenly into another substance (the solvent). In this case, the solid is the solute and water is the solvent.

* Homogeneous: This means the mixture has a uniform composition throughout. You can't visually distinguish the solid from the water anymore.

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