An aqueous solution is a solution in which the solvent is water. This means that it is a mixture of a substance (called the solute) and water (called the solvent).
An aqueous solution can be classified as an acid, base, or neutral based on its pH level. A solution with a pH less than 7 is considered acidic, a solution with a pH greater than 7 is considered basic, and a solution with a pH of 7 is considered neutral.
The concentration of hydrogen ions (H+) in the solution determines its pH. The higher the concentration of H+ ions, the lower the pH and the more acidic the solution. The lower the concentration of H+ ions, the higher the pH and the more basic the solution.
Some common examples of acidic aqueous solutions include lemon juice, vinegar, and battery acid. Basic aqueous solutions include ammonia, bleach, and soap. Water and human blood are examples of neutral aqueous solutions.
The pH of an aqueous solution can be tested using pH paper, which changes color depending on the pH of the solution. Another method is using a pH meter, which provides a more accurate reading of the pH. Additionally, certain indicators such as litmus paper can also be used to determine the pH of a solution.