The pH of ammonia is about 11, which makes it a fairly weak base. According to the pH scale, substances with a pH lower than 7 are acids, whereas those with a pH greater than 7 are bases.
At a pH of 7, pure water is neither an acid nor a base. Ammonia, with its high pH, is a base that is often used as a cleaner or disinfectant. Many bases have varied uses in the cleaning industry.
Ammonia, in its natural state, is a gas deprived of color that has a strong odor. Oftentimes, ammonia is put into a solution for ease of use. This solution consists of 95 percent water. The ammonia used in cleaning solutions is not in its pure form.