A solution having pH equal to zero is known as

The pH scale is a logarithmic measure of the hydrogen ion (H+) concentration in a solution, typically ranging from 0 to 14. A pH of 7 is considered neutral, representing pure water. Solutions with a pH value less than 7 are classified as acidic, while those greater than 7 are alkaline or basic. Because the scale is logarithmic, each unit decrease in pH represents a tenfold increase in acidity. A pH of 0 represents the extreme lower end of the standard scale, indicating a very high concentration of hydrogen ions (1.0 M) [1]. Consequently, a solution with a pH of 0 is characterized as highly acidic [1]. While negative pH values are possible in extremely concentrated strong acids, 0 remains the benchmark for a highly acidic environment in standard chemical contexts.

Sources

1. [1] https://www.epa.gov/goldkingmine/what-ph