One of the mysteries of the English language finally explained.
Definition of alkali in US English:
alkali
nounPlural alkalis
A chemical compound that neutralizes or effervesces with acids and turns litmus blue; typically, a caustic or corrosive substance of this kind such as lime or soda.
Alkalis release hydroxide ions (OH⁻) when dissolved in water. Any solution with a pH of more than 7 is alkaline
‘flint is not subject to chemical weathering except by strong alkalis’mass noun ‘the reaction is followed by measuring the concentration of alkali at various times’- ‘Caustic alkalis react with the paint coating and loosen it from the surface.’
- ‘Tellurium reacts with both acids and some alkalis.’
- ‘Like semi-permanent dyes, permanent dyes are also alkalis.’
- ‘Platinum also dissolves in hot alkalis such as hot sodium hydroxide or potassium hydroxide.’
- ‘Nitriles can be decomposed by acids or alkalis to give the corresponding carboxylic acid or they can be reduced to give primary amines.’
- ‘Zinc is a fairly active metal that dissolves in both acids and strong alkalis.’
- ‘Carboxylic acids also react with alkalis, or bases.’
- ‘It combines with most non-metals at high temperatures and reacts with both acids and alkalis.’
- ‘The high-density overlay protects the wood substrate from alkalis and water.’
- ‘They resist most chemicals, including many acids, alkalis, oxidizing agents, and solvents.’
- ‘Nickel has good resistance to corrosion in the normal atmosphere, in natural freshwaters and in deaerated nonoxidizing acids, and it has excellent resistance to corrosion by caustic alkalis…’
- ‘Concentrated acids and caustic alkalis should be handled with the greatest care.’
- ‘Chemically, aluminum will react with the alkalis in concrete and produce hydrogen bubbles.’
- ‘Amides are hydrolysed to ammonium salts with catalysis by acids or alkalis.’
- ‘Corrosives (mineral acids, alkalis, phenols) are in this category.’
- ‘It can withstand high temperatures and is resistant to many corrosive substances such as acids and alkalis.’
- ‘It accounted for acids and alkalis, for respiration and the smells of plants.’
- ‘On contact, strong acids, alkalis, and heavy metals cause chemical burns.’
- ‘Soap is made by combining a fat source (either animal or vegetable) and an alkali in a chemical process known as saponification.’
- ‘Copper is a moderately reactive metal that dissolves in most acids and alkalis.’
caustic, corroding, eroding, erosive, abrasive, biting, mordant, burning, stingingView synonyms
Origin
Late Middle English (denoting a saline substance derived from the ashes of various plants, including glasswort): from medieval Latin, from Arabic al-qalī ‘calcined ashes (of the glasswort etc.)’, from qalā ‘fry, roast’.