How is a solution defined in terms of mixtures?

A solution is defined as a blended mixture of two or more substances, where one substance (the solute) is dissolved in another (the solvent). This definition captures the essence of what a solution truly is: a homogeneous mixture that displays uniform properties throughout. In a solution, the individual components are not easily distinguishable, and the solute is typically present in a smaller amount compared to the solvent.

This choice effectively encompasses all solutions, which can involve solids, liquids, or gases. For example, when sugar is dissolved in water, the sugar molecules disperse evenly, forming a solution without any visible separation between the sugar and water.

The other answers may not accurately represent the concept of a solution. A simple blend of gaseous substances does not account for the need for solute and solvent components. A mixture that cannot be separated generally implies a compound rather than a solution, and solid mixtures of powder and liquid are more indicative of suspensions or emulsions rather than true solutions. Thus, the chosen answer provides a comprehensive and correct definition of a solution.