sódium

Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium belongs to the alkali metal group and is located in Group 1 of the periodic table. It is the sixth most abundant element in the Earth's crust by mass.

Pure sodium is not found in nature because it is so reactive. Instead, it is found in compounds, most notably sodium chloride (common salt), which is found in seawater and as rock salt. Sodium is also a key component of many other minerals.

In its elemental form, sodium is too reactive to be used commercially. It reacts vigorously with water, producing heat and hydrogen gas, which can ignite. For this reason, it is typically stored under oil or in a vacuum to prevent contact with air and moisture.

Sodium is essential for life. It plays a critical role in maintaining fluid balance, nerve impulse transmission, and muscle function in animals. The human body contains a significant amount of sodium, primarily in the extracellular fluid. Sodium is also an important component of many industrial processes, including the production of dyes, glass, and detergents. It is also used in some types of lighting and as a coolant in nuclear reactors.

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