Here's why:

* The pH scale: Ranges from 0 to 14, with:

* 0 being the most acidic

* 7 being neutral (like pure water)

* 14 being the most alkaline (basic)

* A pH of 1 indicates a very high concentration of hydrogen ions (H+), which are responsible for acidity.

Examples of liquids with a pH of 1:

* Concentrated hydrochloric acid (HCl) is a strong acid commonly used in industrial processes.

* Concentrated sulfuric acid (H2SO4) is another strong acid used in various applications.

Important Note: Working with highly acidic liquids like those with a pH of 1 requires extreme caution due to their corrosive nature.