The word “Alkali” means ?

The term “alkali” has historical significance in chemistry. It comes from the Arabic word “al-qaly”, which translates to “ashes”. In early times, chemists obtained alkalis by extracting soluble salts from plant ashes, especially from species like barilla and kelp. These natural sources were rich in potassium and sodium compounds, which produced basic solutions when dissolved in water.

An alkali is essentially a substance that forms hydroxide ions (OH⁻) in water, making the solution basic. Common examples include sodium hydroxide (NaOH) and potassium hydroxide (KOH). These substances were historically derived from ashes, which explains the origin of the name. When plant ashes were leached with water, the solution contained potash (K₂CO₃) or soda (Na₂CO₃), both of which are alkalis. These early alkalis were important for soap making, glass production, and dyeing.

Over time, the meaning expanded from the literal “ashes” to represent basic substances in general. Chemists recognized that these substances could neutralize acids, produce soaps, and participate in various industrial chemical reactions, which established alkalis as a fundamental concept in inorganic chemistry.

Although alkalis are chemically bases, the word “alkali” specifically refers to their origin from ashes, distinguishing the historical context from the modern chemical definition. It is an example of how etymology and chemistry history are intertwined in terminology.

Therefore, among the given options, the correct answer is ashes (C), reflecting both the historical origin and meaning of the word “alkali.