The world of metals is diverse and interesting. Their properties have long been studied by man, and it is simply impossible to imagine our life without such elements as iron, aluminum, chromium. In our article, we will talk about sodium.
The structure of the sodium atom , the arrangement of electrons by energy levels determine its main characteristics. These, for example, include indicators such as high chemical activity, ductility, ability to conduct heat and electric current.
But special attention should be paid to considering the structure of the elementary particle of the chemical element of sodium - its atom.
The most active and aggressive
Alkali metals, to which sodium belongs, are rightfully considered the most reactive in chemistry. That is why not one of them, including sodium, is found in nature as a nugget, but is in ionic form in rocks and minerals.
These include table salt, sylvinite and carnallite. How can this be explained?
The answer lies in the structural features of the sodium atom. An element, like its counterparts in the subgroup of alkali metals, has a large atomic radius. In addition, its only electron, located at the last energy level, is weakly bound to a positively charged nucleus. Therefore, it is easily detached from the atom itself and captured by particles of other chemical elements. This ability - to easily give away its own electrons - and determines all the main properties of metal elements.
Electronic structure of the sodium atom
The full formula showing the distribution of electrons by energy levels in an atom has the following form: 1s22s 2 2p 6 3s 1 .
The last unpaired electron, forming a sphere-shaped cloud during rotation, is located at a considerable distance from its own nucleus. It is involved in the appearance of a type of bond, such as ionic interaction, and is called valence.
The radius of the atom itself is about 0.189 nm, and its ionization energy is 5.14 eV. Due to this structure of the atom of the sodium element, its simple substance exhibits well-defined reducing properties, that is, in reactions with atoms of other elements it always gives up its only electron located at the last energy level (third).
In this case, the electrically neutral sodium particle turns into a positively charged ion - cation. The pronounced reducing properties of the metal and its chemical activity impose special requirements on the conditions of its storage. So that the metal is not oxidized by atmospheric oxygen, it is stored under a layer of technical oil or kerosene. The electronic circuit of the sodium atom has the following form (see photo below).
Physical properties
What is the relationship between the electronic formula and the physical properties of sodium? The structure of the sodium atom reveals this relationship.
Natural Na consists of only one isotope. It is a very soft silver-white metal that can be cut with a knife. Its density is only 0.97 g / cm.
Like other metals, sodium conducts electric current and heat well. Since in the subgroup of alkali metals the atomic radii and their properties as reducing agents increase with increasing nuclear charge, the boiling and melting temperatures will decrease.
How does the structure of an atom affect the chemical properties of an element?
We continue the study of the structure of the sodium atom. Sodium contains at the third energy level one electron, the electron cloud of which has the shape of a sphere. Therefore, metal is referred to as s-elements, and they are known to easily enter into chemical interaction with non-metals, for example, oxygen, hydrogen, sulfur, nitrogen, etc. When reacting with water, sodium quickly dissolves in it, forming an alkali solution.
The high activity of sodium alkali metal is expressed in the peculiarities of its interaction with acids, which is accompanied by an explosion. Therefore, such a reaction in the laboratory is prohibited. Another feature of metallic sodium is that it does not react with solutions of salts and alkalis, since it itself begins to actively interact with a solvent - water.
So, as you can see, the structure of the sodium atom, as well as its relationship with the physical and chemical properties of the element, are indeed of scientific interest.