Bleach has a pH of 13, which means it is considered a base. The pH scale ranges from 0 to 14, with 7 being neutral. Substances with a pH less than 7 are acids, while those with a pH greater than 7 are bases. Since bleach has a pH of 13, it falls well into the basic range.
Bases are substances that can accept hydrogen ions (H⁺) or donate hydroxide ions (OH⁻). Bleach, which is typically a solution of sodium hypochlorite (NaOCl) in water, is a strong base. It is commonly used for cleaning and disinfecting due to its ability to break down organic materials and kill bacteria and viruses.
In summary, bleach is a base because its pH is significantly higher than 7, making it alkaline.