Chemistry. a soft, silver-white, metallic element that oxidizes rapidly in moist air, occurring in nature only in the combined state, and used in the synthesis of sodium peroxide, sodium cyanide, and tetraethyllead: a necessary element in the body for the maintenance of normal fluid balance and other physiological functions. Symbol: Na; atomic weight: 22.9898; atomic number: 11; specific gravity: 0.97 at 20°C.
Medicine/Medical, Pharmacology. any salt of sodium, as sodium chloride or sodium bicarbonate, present in or added to foods or beverages as a seasoning or preservative and used in many pharmaceutical products as an antacid, anticoagulant, or other agent.
a very reactive soft silvery-white element of the alkali metal group occurring principally in common salt, Chile saltpetre, and cryolite. Sodium and potassium ions maintain the essential electrolytic balance in living cells. It is used in the production of chemicals, in metallurgy, and, alloyed with potassium, as a cooling medium in nuclear reactors. Symbol: Na; atomic no: 11; atomic wt: 22.989768; valency: 1; relative density: 0.971; melting pt: 97.81±0.03°C; boiling pt: 892.9°C
(as modifier): sodium light
sodium so·di·um (sō’dē-əm)
A soft, light, highly reactive metallic element that is naturally abundant, especially in common salt. Atomic number 11; atomic weight 22.99; melting point 97.7°C; boiling point 883°C; specific gravity 0.971; valence 1.
A soft, lightweight, silvery-white metallic element of the alkali group that reacts explosively with water. It is the most abundant alkali metal on Earth, occurring especially in common salt. Sodium is very malleable, and its compounds have many important uses in industry. Atomic number 11; atomic weight 22.99; melting point 97.8°C; boiling point 892°C; specific gravity 0.971; valence 1. See Periodic Table.
noun, Chemistry. 1. a white, crystalline, water-insoluble, flammable powder, NaNH 2 , used chiefly in the manufacture of sodium cyanide and in organic synthesis.
noun, Chemistry. 1. a colorless, odorless, crystalline, water-soluble solid, NaNH 4 HPO 4 ⋅4H 2 O, originally obtained from human urine: used as a blowpipe flux in testing metallic oxides.
noun, Chemistry. 1. a white or grayish-white, water-soluble, poisonous powder, NaAsO 2 , used chiefly in arsenical soaps for hides, as an insecticide, and as a weed-killer.
noun, Chemistry, Pharmacology. 1. a white, crystalline or granular, water-soluble powder, C 7 H 5 NaO 2 , used chiefly as a food preservative and antifungal agent, and in diagnostic tests of liver function. sodium benzoate noun 1. a white crystalline soluble compound used as an antibacterial and antifungal agent in preserving food (E211), as […]