What is Sodium? | Types, Definition, Structure, Function & Facts

What is Sodium?

Sodium is an alkali metal located in the first group or column of the periodic table. The sodium atom has 11 electrons and 11 protons with one valence electron in the outer shell.

Characteristics and Properties

Sodium in its pure form is very reactive. It is a very soft metal that can be easily cut with a knife. It is silvery white and burns with a yellow flame.

Sodium will float on water, but it will also react violently when in contact with water. When sodium reacts with water, it produces sodium hydroxide and hydrogen gas.

Sodium is best known for its many useful compounds such as table salt (NaCl), sodium nitrate (Na2CO3) and baking soda (NaHCO3). Many compounds formed by sodium are water-soluble, that is, they dissolve in water.

Highlights of Sodium:

Symbol Na
Atomic Number 11
Atomic Weight 22.99
Classification Alkali metal
Phase at Room Temperature Solid
Density 0.968 grams per cm cubed
Melting Point 97.72°C, 207.9°F
Boiling Point 883°C, 1621°F
Discovered by Sir Humphry Davy in 1807

Where is Sodium found on Earth?

Sodium is the sixth most abundant element on Earth. It is never found in its pure form because it is very reactive. It is found only in compounds such as sodium chloride (NaCL) or table salt. Sodium chloride is found in seawater (salt water), salt lakes and underground sediments. Pure sodium can be recovered from sodium chloride by electrolysis.

How is Sodium used Today?

Sodium is mainly used in compounds with other elements.

The average person uses sodium every day in the form of table salt in their diet. Table salt is the compound sodium chloride (NaCl). Table salt is essential for the survival of animals, but most people use it to add flavor to their food.

Another common use of sodium is in baking soda, the chemical compound of sodium bicarbonate. Baking soda is used as a leavening agent in baked goods such as pancakes, cakes, and breads.

Many soaps are salts of sodium. Sodium hydroxide is a key ingredient in soap making.

Other uses include defrosting, medicine, organic chemistry, street lighting and nuclear reactor cooling.

How was it Discovered?

Sodium was discovered by British chemist Sir Humphry Davy in 1807. He isolated sodium by electrolysis with caustic soda.

Where did Sodium get its name?

Sodium was discovered by British chemist Sir Humphry Davy in 1807. He isolated sodium by electrolysis with caustic soda.

Isotopes

Only one of the 20 known isotopes of sodium is stable, sodium-23.

Interesting Facts about Sodium

Sir Humphry Davy discovered sodium just days after the discovery of potassium.
Sodium makes up about 2.6% of the earth’s crust.

It helps to maintain the proper water balance in the cells of the body and also helps us digest food.

Our bodies lose sodium when we sweat. However, most people consume more sodium than their bodies actually need. A lack of sodium in the body can cause muscle cramps.

Sodium is considered non-toxic, but too much can cause high blood pressure.