(British spelling, inorganic chemistry) A colourless highly corrosive liquid, H₂SO₄.

(organic chemistry) Any of a class of organic compounds containing a carboxyl functional group.

(organic chemistry) 2-hydroxy-propanoic acid (CH₃.CHOH.CO₂H), a syrupy liquid, soluble in water; found in milk, wine and many fruits; used as a food additive and in many industrial applications.

(biochemistry) A white crystalline organic compound, C₆H₈O₆, found in citrus fruits and many vegetables; it is an antioxidant and an efficient scavenger of free radicals.

(organic chemistry) A liquid fatty acid, CH₃(CH₂)₄COOH, obtained from animal fats, and used in the manufacture of pharmaceuticals and flavours.

(organic chemistry) An aromatic heterocyclic organic compound, C₃N₃(OH)₃, that decomposes on heating to form cyanic acid; it is a prebiotic compound found in stellar dust clouds.

(organic chemistry) A white crystalline organic compound, N-cyclohexylsulfamic acid, whose salts, the cyclamates, have been used as artificial sweeteners

(biochemistry) A nonessential amino acid, L-α-amino-succinic acid, aminobutanedioic acid, found in animal protein and in sugar beet etc.

(organic chemistry) A long chain unsaturated fatty acid, CH₃(CH₂)₇CH=CH(CH₂)₁₁COOH, found in rapeseed and mustard seed oils; the cis- isomer is erucic acid, the trans- isomer is brassidic acid

(inorganic chemistry) the acid formally derived from sulphuric acid by replacing a hydroxyl (-OH) group by an amino (-NH₂) group - SO₂(OH)(NH₂)