Sodium and Preparation of Sodium
Sodium is a chemical element with the symbol Na and atomic number 11. It is a soft, silvery-white, highly reactive metal. Sodium is an alkali metal, being in group 1 of the table of elements. Its only steady isotope is ²³ Na. The free metal does not take place in nature and should be prepared from compounds. Salt is the 6th most common element in the world and makes up 2.6% of the Earth’s crust.
The most common compound is sodium chloride. This extremely soluble salt has seeped into the oceans over the lifetime of the world, however many salt beds or ‘lakes’ are found where ancient seas have actually evaporated. It is likewise discovered in numerous minerals including cryolite, zeolite, and sodalite. Because sodium is so reactive it is never discovered as a metal in nature. Sodium metal is produced by electrolysis of dry molten sodium chloride.
Chemical Preparation of Salt by Downs Cell
Most salt metal is produced by the electrolysis of fused sodium chloride. Given that the melting point of sodium chloride is 801 ° C, some calcium chloride is contributed to decrease its melting point and to permit the furnace to run at about 600° C.
In the electrolytic cell, the large block of graphite at the center is the anode, above which there is a dome for the collection of chlorine. The cathode is a circular bar of copper or iron which surrounds the anode but is separated from it by an iron screen, which terminated in a gauze. The arrangement permits the electric current to pass freely but prevents sodium and chlorine from mixing after they have actually been emitted at the electrodes.
Sodium metal increases in a special compartment from which it is taken out at intervals.
Advantages of Cell
The cell produces dry chlorine and 99.9 percent pure sodium. The procedure is performed at 600 ° C and it has the following advantages.
- (a) The metallic fog is not produced.
- (b) Liquid sodium can easily be collected at 600 ° C.
- (c) Product of the cell is not attacked by the products formed throughout the electrolysis.
Reactions in Cell
During the process the following reactions occur:
NaCl à Na+ + Cl–
Na+ + e–à Na
Cl- à ½ Cl2 + 1e–
Properties of Sodium
- Sodium at standard temperature and pressure is a soft silvery metal that combines with oxygen in the air and forms grayish white sodium oxide unless immersed in oil or inert gas, which are the conditions it is typically kept in.
- Sodium metal can be easily cut with a knife and is an excellent conductor of electrical energy and heat because it has only one electron in its valence shell, leading to weak metal bonding and totally free electrons, which carry energy.
- In a flame test, sodium and its substances glow yellow.
- Twenty isotopes of sodium are known, but only 23Na is stable.
- Because of the high polarity of the C-Na bonds, they act as sources of carbanions (salts with organic anions). Some well-known derivatives include salt cyclopentadienide (NaC5H5) and trityl cyclopentadienide((C6H5) 3CNa).
Uses of Sodium
- Sodium is used as a heat exchanger in some nuclear reactors, and as a reagent in the chemicals industry. However, sodium salts have more usages than the metal itself.
- The most typical compound of sodium is sodium chloride (common salt). It is added to food and utilized to de-ice roads in the winter season. It is likewise utilized as a feedstock for the chemical industry.
- Sodium carbonate (washing soda) is also a useful sodium salt. It is utilized as a water softener.
- Sodium is important to all living things, and humans have actually known this given that prehistoric times. Our bodies contain about 100 grams, but we are continuously losing salt in different methods so we need to replace it. We can get all the sodium we need from our food, without including any extra. The average individual consumes about 10 grams of sodium a day, however, all we actually require has to do with 3 grams. Any extra sodium might contribute to hypertension. Sodium is essential for several functions of the body. For instance, it assists cells to transmit nerve signals and control water levels in tissues and blood.
- It also utilized in improving the structure of certain alloys; soaps, filtration of molten metals, and sodium vapor lights.
- Sodium is essential in the manufacturing of natural substances and in making esters.
- Solid sodium carbonate is needed in making glass.
Frequently Asked Questions
Q1: What are the products of Down’s cell?
Ans: The products obtained at the end are dry chlorine and 99.9% pure sodium.
Q2: Why calcium chloride is added in Down’s cell?
Ans: The melting point of sodium chloride is 801 ᵒC so to lower its melting point and to operate the furnace at 600 ᵒC calcium chloride is added.
Q3: Why sodium is needed?
Ans: Sodium is required in the manufacture of glass, esters, natural compounds. It is the constituent of table salt used in cooking and as a preservative.