Tabla Periódica: Entendiendo Grupo 1, Grupo 2 y Número Total de Elementos

Periodic Table: Understanding Group 1, Group 2, and Total Number of Elements

The Periodic Table is a fundamental tool in chemistry, used to organize the elements based on their chemical properties. It provides valuable insights into the structure and behavior of various elements. Let's explore the concept of Groups, specifically Group 1 elements and Group 2 elements, as well as the total number of elements recognized today.

Group 1 Elements (Alkali Metals)

Group 1 is commonly referred to as the alkali metals. These elements are highly reactive due to having one valence electron, which is easily lost to form a positively charged ion. The alkali metals include lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). Alkali metals react readily with halogens to form ionic salts, such as table salt, sodium chloride (NaCl). Their reactions with water release hydrogen gas, which can ignite the released hydrogen and lead to dangerous situations.

Group 2 Elements (Alkaline Earth Metals)

Group 2 elements, also known as alkaline earth metals, consist of beryllium (Be), magnesium (Mg), calcium (Ca), strontium (Sr), barium (Ba), and radium (Ra). Like the alkali metals, they are reactive but less so due to having multiple valence electrons. The group 2 elements have a lower ionization energy than the corresponding period 3 metals, making them more active. They are also soft enough to cut with a knife.

Total Number of Elements

According to the Los Alamos National Laboratory, chemists officially recognize 118 elements, with four new additions in 2016. However, some variation in group names and membership still exists, particularly regarding the placement of the inner transition metals. Despite this, the system of eighteen groups is generally accepted by the chemistry community.