Which of the following pH levels indicates a highly acidic solution?

The pH scale ranges from 0 to 14, with lower values indicating higher acidity and higher values indicating alkalinity. A pH level of 7 is considered neutral. When considering solutions, a pH level below 7 suggests increasing acidity, with lower numbers correlating to greater acidity.

A pH of 3 falls significantly below the neutral point of 7, indicating a strongly acidic solution. Common examples of substances with a pH of around 3 include vinegar and citrus juices, which are recognized for their acidic properties. In contrast, a pH of 6 is closer to neutral and indicates only a mild acidity, while values like 8 and 9 represent alkaline environments.

Thus, among the choices, a pH of 3 distinctly characterizes a highly acidic solution, making it the correct answer.