Tabla de Contenidos
This article presents the meaning of each of the numbers that accompany the elements of the periodic table . In addition, we will see how to more easily identify the elements that make up the periodic table.
the periodic table
The first thing that is observed in the table, especially from a distance, is that each box corresponds to a single element and that, in turn, each one of these occupies its place permanently. The periodic table shows us the elements classified according to the similarity of their physical and chemical properties. That is why we can notice that there are groups with a particular color.
Then we will notice that in each of the cells of each element there is a large capital letter or an abbreviation started in capital letter that bears the name of the element below. This letter or abbreviation is called the chemical symbol and is the conventional way of referring to the element in question in writing; it is much shorter and more practical than using the full name.
Details to consider
- There is no standardized or mandatory layout for the cells of each element. The numeric values in the cells of a particular table can be anywhere in the cell. Identifying what number it is is easy because it is whole numbers or decimals.
- What is standardized is the arrangement of the cells of the elements, as well as the arrangement of the groups in which they are classified.
- The level of detail for each table also varies; There are more detailed tables than others depending on the purpose they serve. The highly detailed tables are useful for doing chemical equations without having to remember all the facts for each element.
- Sometimes you can get the impression that an element is in the wrong place. It can be the same element only its alternative name is used in this particular table.
The most common numbers on the periodic table
One of the most commonly seen numbers on a periodic table is the atomic weight value, also known as the atomic mass or mass number. This number corresponds to a single atom of the element in question. It is the sum of the number of protons, neutrons and electrons in the atom of the element, in addition to the ratio of the average of the masses of the atoms that make it up with respect to the twelfth part of a unified atomic mass unit. It is a decimal and, depending on the decision of the person who prints the table, it can be presented in a very detailed number of figures. It is usually seen that many tables consider including up to ten thousandths of the atomic mass. Two examples are the atomic mass of nickel, which is 58.6934, or that of hydrogen, which is 1.0079.
Another of the numerical values frequently included in the periodic table is the atomic number, which is the number of protons that the element in question has. The atomic numbers of the elements are integer values and in many periodic tables this is the largest number we can appreciate. We can also notice how the elements are arranged from lowest to highest atomic number, starting from left to right and from top to bottom in the table. For example, oganeson, which is the heaviest element with atomic number 118, is at the bottom of the table. Hydrogen, for its part, has the 1.
The arrangement of the elements
As mentioned above, each of the elements is part of a group in the periodic table , a group that in turn also corresponds to a color; this makes it easy to locate them. Elements in the same group that are closer together will have similar valences and therefore some properties in common. Understanding this arrangement must be accompanied by a brief exploration of the properties that each element of a shares with each other.
- The columns in the periodic table are called “groups” or “family” and the rows are called “periods”.
- The elements in the table are divided into three broad categories: metals, metalloids, and nonmetals.
The most abundant elements in nature are metals and they are subdivided into 6 subgroups: alkaline (column 1), alkaline earth metal (column 2), transition metals / Block D (columns 3 to 12), lanthanides (row 6), actinides and other metals (columns 13 to 16). Then we have the metalloids (columns 14 to 16). Finally, there are the non-metals, which are subdivided into other non-metals (columns 14 to 16), halogens (column 17) and noble gases (column 18).
References
- Goya, Roman, Elguero (2019). What do we know about the periodic table of elements. Available at: https://books.google.co.ve/books?id=ZiyODwAAQBAJ&printsec
- Chemistry and Society (2019). The ABC of the periodic table. Available at: https://www.quimicaysociedad.org/pdf/Dossier-ABC-Tabla-Periodica.pdf
