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1. . BY Brhane Amha Chemical engineering .

2. Sodium -Magnesium and Aluminum

3. Sodium -Na
Introduction :
 Is chemical element with atomic number 11 .
 It is a soft, silvery-white, highly reactive metal.
 It was 1st electrolyzed from NaOH by Humphrey Davy in 1807.
 Sodium is an, Alkali metal being in group 1 of the periodic table,
because it has a single electron in its outer shell that it readily donates,
creating a positively charged ion—the Na+ cat ion.
 Its only stable isotope is 23Na.
 an abbreviation of the element's New latin name natrium, which
refers to the Egyptian natron.

4. Occurrence
 The Earth's crust contains 2.27% sodium, making it the 7th
most abundant element on Earth.
 5th most abundant metal, behind aluminum, iron, calcium,
and magnesium and ahead of potassium.
Sodium's estimated oceanic abundance is 1.08×104milligrams
per liter.
Because of its high reactivity, it is never found as a pure
element.
The insolubility of certain sodium minerals such
as cryolite and feldspar arises from their polymeric anions,
which in the case of feldspar is a polysilicate.

5. Physical properties

6. Count’…

7. Chemical properties
Sodium is a very active element.
 It combines with oxygen at room temperature.
When heated, it combines very rapidly, burning with a brilliant golden-yellow
flame.
 Sodium also reacts violently with water.
 It is so active that it is normally stored under a liquid with which it does not react.
Kerosene or naphtha are liquids commonly used for this purpose.
Sodium also reacts with most other elements and with many compounds. It reacts
with acids to produce hydrogen gas.
 It also dissolves in mercury to form a sodium amalgam. An amalgam is an alloy of
mercury and at least one other metal.

8. Extraction and Industrial process
pure sodium metal is by passing an electric current through molten
(melted) sodium chloride ( Downs cell process).
But there is not much demand for sodium metal.
Sodium compounds are much more common.
A second and similar method is used to make a compound known as
sodium hydroxide (NaOH).
The sodium hydroxide is then used as a starting point for making other
sodium compounds

9. Extraction and Industrial process
Metallic sodium is produced carbothermal reduction of sodium
carbonate at 1100 °C, as the first step of the Deville process for the
production of aluminum:
Sodium is now produced commercially through the electrolysis of
molten sodium chloride.
This is done in a Downs cell in which the NaCl is mixed with calcium
chloride to lower the melting point below 700 °C.

10. DOWN CELL PROCESS
The Downs' process is an electrochemical method for the commercial
preparation of metallic sodium, in which molten NaCl is electrolyzed in a
special apparatus called the Downs cell.
The Downs cell uses a carbon anode and an iron cathode.
The electrolyte is sodium chloride that has been heated to the liquid state.
Although solid sodium chloride is a poor conductor of electricity,
when molten the sodium and chloride ions are mobilized, which become
charge carriers and allow conduction of electric current

11. Electrolysis of molten Sodium chloride

12. DOWN CELL PROCESS
The Downs' process is an electrochemical method for the commercial
preparation of metallic sodium, in which molten NaCl is electrolyzed in a
special apparatus called the Downs cell.
The Downs cell uses a carbon anode and an iron cathode.
The electrolyte is sodium chloride that has been heated to the liquid state.
Although solid sodium chloride is a poor conductor of electricity,
when molten the sodium and chloride ions are mobilized, which become
charge carriers and allow conduction of electric current

13. Chemical compositions
 The calcium does not enter into the reaction because its reduction potential of
-2.87 volts is lower than that of sodium, which is -2.71 volts. Hence the
sodium ions are reduced to metallic form in preference to those of calcium.
High amount of heat is

14. Half reactions in Down cell process.

15. Sodium compounds

16. APPLICATIONS
 Liquid sodium is used as a heat transfer fluid in some types of nuclear
reactors because it has the high thermal conductivity and low neutron
absorption cross section required to achieve a high neutron flux in the
reactor.
Sodium chloride is extensively used for anti-icing and de-icing and as a
preservative; sodium bicarbonate is mainly used for cooking.
 Metallic sodium is used mainly for the production of sodium
borohydride, sodium azide, indigo, and triphenylphosphine.
 sodium is used in various reactions such as the Birch reduction, and
the sodium fusion test is conducted to qualitatively analyse compounds.

17. APPLICATIONS…..
Lasers emitting light at the sodium D line are used to create artificial laser
guide stars that assist in the adaptive optics for land-based visible light
telescopes.
BIOLOGICAL ROLE:
 regulates blood volume, blood pressure, osmotic equilibrium and pH;
the minimum physiological requirement for sodium is 500 milligrams per
day .
Reduction of blood pressure and sodium concentration in the kidney
result in the production of renin .
In C4 plants, sodium is a micronutrient that aids metabolism, specifically
in regeneration of phosphoenolpyruvate.

18. Safety and precautions
Ingestion and contact with moisture on skin, eyes or mucous
membranes can cause severe burns.
Sodium spontaneously explodes in the presence of an oxidizer such as
water.
Fire extinguishers based on water accelerate sodium fires; those based on
carbon dioxide and bromochlorodifluoromethane should not be used on
sodium fire.
 An effective extinguishing agent for sodium fires is Met-L-X
Other effective agents include Lith-X, which has graphite powder and
an organophosphate flame retardant, and dry sand.