The periodic table exists to organize elements that have similar chemical and physical properties. Metals, semi-metals, non-metals and noble gases form subdivided groups to facilitate localization.
But the Periodic Table is not only useful to know about the atomic mass, atomic number and electronic distribution of atoms, we can use it to observe the periodic and aperiodic properties that are used to relate the characteristics of elements to their structures. atomic.
Let's look at each one in particular:
Periodic properties: occur as the atomic number of a chemical element increases, that is, it assumes values that increase and decrease in each period of the Periodic Table.
Periodic properties include: atomic radius, ionization energy, electroaffinity, electronegativity, density, melting and boiling temperature, and atomic volume.
Demonstration: the periodic property electronegativity grows from the bottom to the top and from the left to the right of the table, since the smaller an atom the greater its electronegativity.
aperiodic properties: the values of this property vary as the atomic number increases, but they do not obey the position in the table, that is, they are not repeated in regular periods.
Examples of aperiodic properties: specific heat, refractive index, hardness and atomic mass. It is worth noting that the atomic mass always increases according to the atomic number of the element, and does not concern the position of this element in the Table.
By Líria Alves
Graduated in Chemistry
Brazil School Team
See more:
Periodic Properties
Periodic table - Chemistry - Brazil School
Source: Brazil School - https://brasilescola.uol.com.br/quimica/propriedades-periodicas-aperiodicas.htm