Alkalisch

Alkalisch is a German adjective used to describe chemical bases and environments with alkaline properties. In everyday and scientific use, it denotes substances, solutions, or soils with a pH above 7 or the capacity to neutralize acids. The term is closely related to alkaline and basic, but in German usage alkalisch often implies a connection to alkali-related chemistry or hydroxide formation when dissolved in water.

In chemistry, alkalis are bases that dissolve in water to yield hydroxide ions. Common alkalis include sodium hydroxide (caustic soda), potassium hydroxide, and calcium hydroxide (slaked lime). Bases that do not form hydroxide in water are described as basic but not alkaline. Alkaline solutions typically have a pH well above 7 and can be corrosive, requiring appropriate safety precautions. The term is also applied to environments, such as alkaline soils or alkaline waters, where high pH affects solubility and biological activity.

In geology and mineralogy, alkalisch describes rocks with a high content of alkalis (alkali metals and related compounds). These “alkaline rocks” include various compositions that are rich in sodium and potassium and are contrasted with more silica-saturated or alkaline-poor rocks. The word’s etymology traces to alkali, from Arabic al-qaly (ashes), through Latin and French into German.