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symbol of sodium

Sodium

Sodium is the 11th element of Periodic table with atomic number 11, atomic weight 22.98977. S Symbol Na, has a Body Centered Cubic structure and Silver color. Sodium is a alkali metal element. Trivial name of Sodium is alkali metals. Know everything about Sodium Facts, Physical Properties, Chemical Properties, Electronic configuration, Atomic and Crystal Structure.

image of sodium element

History of Sodium

The element Sodium was discovered by Humphry Davy in year 1807 in United Kingdom. Sodium derived its name from the English word soda (natrium in Latin)

Sodium /ˈsoʊdiəm/ is a chemical element with symbol Na (from Ancient Greek Νάτριο) and atomic number 11. It is a soft, silver-white, highly reactive metal. In the Periodic table it is in column 1 (alkali metals), and shares with the other six elements in that column that it has a single electron in its outer shell, which it readily donates, creating a positively charged atom – a cation.

How to Locate Sodium on Periodic Table

Periodic table is arranged by atomic number, number of protons in the nucleus which is same as number of electrons. The atomic number increases from left to right. Periodic table starts at top left ( Atomic number 1) and ends at bottom right (atomic number 118). Therefore you can directly look for atomic number 11 to find Sodium on periodic table.

Another way to read periodic table and locate an element is by using group number (column) and period number (row). To locate Sodium on periodic table look for cross section of group 1 and period 3 in the modern periodic table.

Sodium Facts

Name
Sodium
Atomic Symbol
Na
Atomic Number
11
Atomic Weight
22.98977
Phase
Solid
Colour
Silver
Classification
Alkali Metal
Group in Periodic Table
1
Group Name
lithium family
Period in Periodic Table
3
Block in Periodic Table
s-block
Electronic Configuration
[Ne] 3s1
Melting Point
97.72 °C
Boiling Point
883 °C
Electronic Shell Structure
[2, 8, 1]
CAS Number
CAS7440-23-5

Sodium Atomic Structure and Orbital Properties

Sodium atoms have 11 electrons and the electronic shell structure is [2, 8, 1] with Atomic Term Symbol (Quantum Numbers) 2S1/2.

sodium atomic structure
sodium isotopes

Element Properties

Atomic Number
11
Number of Protons
11
Mass Number
23
Number of Neutrons
12
Shell structure (Electrons per energy level)
[2, 8, 1]
Electron Configuration
[Ne] 3s1
Valence Electrons
3s1
Oxidation State
-1 1
Atomic Term Symbol (Quantum Numbers)
S1/2

Atomic Structure of Sodium

Atomic Radius
190 pm (1.9 Å)
Atomic Volume
23.7497623967 cm3
Covalent Radius
154 pm (1.54 Å)
Van der Waals Radius
227 pm
Neutron Cross Section
0.53 σa/barns

Ground State Electronic Configuration of Sodium - neutral Sodium atom

The ground state electronic configuration of Neutral Sodium atom is [Ne] 3s1. The portion of Sodium configuration that is equivalent to the noble gas of the preceding period, is abbreviated as [Ne]. For atoms with many electrons, this notation can become lengthy and so an abbreviated notation is used.This is important as it is the Valence electrons 3s1, electrons in the outermost shell that determine the chemical properties of the element.

Unabbreviated electronic configuration of neutral Sodium

Complete ground state electronic configuration for the Sodium atom, Unabbreviated electronic configuration

1s2 2s2 2p6 3s1

Atomic Spectrum of Sodium

Atomic Spectrum of Sodium

Regulatory and Health - Health and Safety Parameters and Guidelines

CAS Number
CAS7440-23-5
RTECS Number
RTECSVY0686000
EU Number
EU231-954-8
DOT Hazard Class
4.3
DOT Numbers
1428
NFPA Fire Rating
3
NFPA Hazards
Water Reactive
NFPA Health Rating
3
NFPA Reactivity Rating
2
Autoignition Point
115 °C
Flashpoint
4 °C

Sodium Chemical Properties : Sodium Ionization Energies and electron affinity

Valence
1
ElectronAffinity
52.8 kJ/mol
Electronegativity
0.93

Use of Sodium

Sodium is used as a heat exchanger in some nuclear reactors, and as a reagent in the chemicals industry. But sodium salts have more uses than the metal itself. The most common compound of sodium is sodium chloride (Nacl). It is added to food and used to de-ice.