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.Often contrasted with acid; compare with base1 .
•Adlai • gadfly • blackfly • damselfly
•sandfly • barfly • mayfly
•greenfly • bacilli • multiply • styli
•whitefly • wall eye • horsefly
, E. coli, gladioli
•blowfly • lapis lazuli
• reguli • stimuli
•flocculi • ranunculi • firefly
•discoboli • astragali • dragonfly
•alkali • Lorelei • Naphtali • butterfly
that reacts with an acid
to form a salt
and water. A solution of an alkali has a pH greater than 7. Alkali solutions are used as cleaning materials. Strong alkalis include the hydroxides of the alkali metals
and ammonium hydroxide. The carbonates of these metals are weak alkalis.
†soda ash XIV; saltwort, Salsola kali
XVI; any substance having the properties of soda XVII; (mod. chem.) hydroxide of sodium, potassium, etc. XIX. — medL. — Arab. al-ḳily
calcined ashes, f. ḳalā
fry, roast; see AL-2
. Cf. F. alcali
XVII; cf. F. alcalin
XIX. — G.
alkali (or base)
A compound that takes up hydrogen ions and so raises the pH
of a solution; see also acid
alkali (al-kă-ly) n.
a base that is soluble in water. Alkaline solutions turn litmus paper blue. See base
that dissolves in water to give hydroxide ions (OH–