A solution is defined as...

• A. Mixture of two or more mutually miscible substances
• B. A pure substance
• C. A suspension
• D. A chemical element

Answer: (A)

A solution is a homogeneous mixture formed when a solute dissolves in a solvent, producing a single, uniformly mixed phase. When two or more substances are mutually miscible, they can mix completely to form that uniform phase, which is why a mixture of two or more miscible substances is the correct definition of a solution.

This differs from a pure substance, which has a single, uniform composition and is not a mixture. It also differs from a suspension, where particles are large enough to be seen and will settle out over time, not forming a single uniform phase. It also differs from a chemical element, which is made of only one type of atom and is not a mixture. For example, salt dissolved in water or ethanol in water are solutions because the components form one consistent phase throughout.