An aqueous solution has a pH of 7.3. This solution is considered to be:

A solution with a pH of 7.3 is classified as slightly basic because the pH scale ranges from 0 to 14. A pH of 7 is considered neutral, which indicates equal concentrations of hydrogen ions (H⁺) and hydroxide ions (OH⁻). Any pH value above 7 signifies a higher concentration of hydroxide ions than hydrogen ions, leading to a basic character.

Since 7.3 is just slightly above 7, it shows that the solution has a small excess of hydroxide ions, which makes it slightly basic. In contrast, a pH below 7 would suggest acidity, with decreasing values indicating increasing acidity, while a neutral solution remains at pH 7. Therefore, the classification of the solution as slightly basic aligns with its pH value being above neutral but not significantly so.