|a. 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|
|b. (as modifier): sodium light|
|[C19: New Latin, from |
|any saline or salty solution|
|a compound capable of changing state or becoming inactive when subjected to heat or radiation|
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.
|sodium (sō'dē-əm) Pronunciation Key
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.