INORGANIC CHEMISTRY
A  B  C  D  E  F  G  H  I  J  K  L  M  N  O  P  Q  R  S  T  U  V  W  X  Y  Z

                  
  • HOME
  • ABOUT
  • CATEGORIES
  • SITE MAP
  • COPYRIGHT
  • ADVERTISE
  • CONTACT
    •

    entire Web this site



    sodium (Na)

    sodium
    Sodium. Credit: Justin Urgitis, wikipedia
    A soft, light, extremely malleable, metallic element that reacts explosively with water. Sodium is one of the alkali metals. It is naturally abundant in combined forms, notably in common salt (sodium chloride), and is present in a wide variety of important compounds. Sodium is the fourth most abundant element on Earth and makes up about 2.6% of the crust by weight. It was first isolated by Humphry Davy in 1807 by electrolysis of caustic soda.


    atomic number 11
    relative atomic mass 22.98977
    electron configuration 1s22s22p63s1
    atomic radius 144.4 pm
    oxidation state 1
    melting point 97.8 °C (208.4 °F)
    boiling point 892 °C (1,638 °F)
    relative density 0.968


    Sodium and life

    Sodium in the body helps regulate water balance, helps maintain normal heart rhythm, and is involved in the conduction of nerve impulses and the contraction of muscles (see sodium-potassium pump. The body of an average-sized person contains about 55 grams of sodium. The level of sodium in the blood is controled by the kidneys, which eliminate any excess via the urine.

    Almost all foods contain sodium naturally or as an ingredient added during processing or cooking. The principal forms f sodium in food are sodium chloride (table salt) and sodium bicarbonate (baking soda). Apart from table salt, the main dietary sources of sodium are processed foods, cheese, breads and cereals, and smoked, pckled, or cured meats and fish. Pickles and snack foods contain large amounts.

    Most Western diets contain too much sodium. The average daily consumption is 3 to 7 grams, compared with a maximum recommended intake of 1 to 3 g. Excess sodium intake is a contributary factor in the high incidence of high blood pressure (hypertension) in the Western countries. Sodium deficiency, on the other hand is rare, but may be caused by persistent diarrhoea or vomiting, through profuse sweating, or through prolonged or excessive treatment with diuretic drugs.


    Related category

       • INORGANIC CHEMISTRY



    Also on this site:

    Encyclopedia of Alternative Energy & Sustainable Living
    Encyclopedia of History
    Transport Concepts & Designs (partner site)


    BACK TO TOP