Characteristics of sodium
Sodium is the element of the periodic table of symbol Na and atomic number 11. This means that its nucleus is formed by 11 protons (apart from neutrons), with 11 electrons orbiting them. Sodium is an alkali metal, and it is highly reactive. At room temperature, this element is a silvery-white metal that can easily be cut with a knife.
Sodium becomes liquid at 97.8ºC, but it isn’t until 880ºC that it turns into a gas. This element is very good electricity and heat conductor.
Sodium is the sixth most abundant element on Earth and forms about 2.8% of the Earth’s crust. As sodium is highly reactive, it is never found in its pure form in nature and forms compounds with a great variety of elements. The most common compound of sodium is salt, but it is also found in many minerals, such as cryolite or zeolite.
Uses of the element
- Sodium in its liquid state is a very good heat exchanger, and it is used as a coolant in some nuclear reactors.
- Sodium vapour is used in streetlights, producing a brilliant yellow light.
- Significant quantities of sodium are used in the production of synthetic detergents and perfumes.
- Salt, which is a compound of sodium, is used in food, to de-ice roads in winter and as a food preservative of food.
Being highly reactive, sodium isn’t found freely in nature. Even if compounds of this metal are known for thousands of years ago, it wasn’t until 1807 that it was first isolated. The author of this discovery was Sir Humphry Davy through the electrolysis of sodium hydroxide.
The name of this element comes from the Latin word “sodanum”, which means “headache remedy”.