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- Name : Sodium
- Symbol : Na
- Atomic # : 11
- Atom weight: 22.9898
- Melting P. : 97.81
- Boiling P. : 882.9
- Oxidation : +1
- Pronounced : SO-di-em
- From : Medieval Latin sodanum, "headache remedy"
- Identified : Sir Humphry Davy in 1807
- Appearance : Soft, silvery-white metal
- Note : Burns in air with a brilliant white flame
-
- [Properties]
-
- Sodium is a very soft, silvery-white metal. It looks very much like
- aluminum, but is much softer; it is so soft, in fact, that it can be easily
- cut with a knife. However, few people have a chance to see and work with
- pure sodium metal on a regular basis. The compounds are all over the place,
- but the metal itself has virtually no practical application and does not
- adapt readily to normal environmental conditions. For example, it reacts
- vigorously with atmospheric oxygen to form sodium peroxide, and reacts
- violently with water to form hydrogen and sodium hydroxide.
- Sodium belongs to the alkali metals of Group IA on the periodic table of
- elements. Hydrogen (H) is grouped with these metals and they have a number
- of features in common - except one very important feature: hydrogen is a
- gas. The Group IA metals are known as alkali metals because they form very
- strong and caustic (or alkaline) compounds with the OH- ion. Common
- household lye, for example, is potassium or sodium hydroxide. Lithium
- hydroxide is even nastier, and far too dangerous for household use.
- Sodium alloys with three other metals in its group to form an important
- and unusual series of eutectic metals. Recall that an alloy is a mixture
- of two or more metals. An eutectic system is a mixture of substances whose
- melting point is lower than that of any of the individual parts.
- Sodium and its salts impart a yellow color to a flame test.
-