* No new substances are formed: The drink's components (sugar, flavorings, etc.) and the water molecules simply mix together. They don't change their chemical makeup.

* The change is reversible: You can separate the drink from the water by boiling off the water, leaving the drink components behind.

* The change is usually a matter of distribution: The drink particles spread out and become evenly distributed throughout the water.

Exceptions:

* Some drinks may undergo slight chemical reactions. For example, some powdered drinks may release small amounts of gas when mixed with water.

* If the drink contains an acidic ingredient (like lemon juice), it might slightly react with the water, leading to a very minor chemical change.

In summary: While there may be a tiny chemical component, the dominant change when you mix a drink into water is a physical one.