PERIODIC TABLE OF ELEMENTS – Meaning Of The Table And How The Elements Are Grouped
PERIODIC TABLE OF ELEMENTS – In this topic, we will discus the periodic table of elements and how the elements are grouped.
Meaning
It is a display of the chemical elements in the form of a table, which are arranged by atomic number, electron configuration, and recurring chemical properties.
The table was created by Russian chemist Dmitri Mendelev, in which at that time, there are 60 discovered elements overall. As of today, the total number of elements discovered and recognized are 118, using Mendelev’s table to organize these elements.
Here is the table:
The elements are divided into groups. Here are the following:
- Alkali Metals – The first group, thus, the first column of the table. These elements are shiny and soft enough for you to use a knife to cut. Alkali metals are also extremely reactive and will burst into flame or even explode on contact with water. Hydrogen, the first element, was added in the group despite being a nonmetal.
- Alkaline-eartth metals – The second group. These hav two electrons in its outermost energy level, thus, making them rare to be found alone in nature.
- Lanthanides – The third group in which, it was too long to fit inside the table, so it was broken out and flipped sideways to form the top of what we call the inner transition metals. These elements have a silvery white color and tarnish on contact with air.
- Actinides – The bottom half of the inner transition metals and the fourth group. They are all radioactive.
- Transition metals – These elements are described as hard but malleable, shiny, and possessing good conductivity.
- Post-transition metals – They have similar characteristics to transition metals, but they tend to be softer and conduct more poorly than other transition metals.
- Metalloids – These elements represent the gradual transition from metals to nonmetals and sometimes behave as semiconductors. They are also known as poor metals.
- Nonmetals – They are literally elements that are not metal, including Hydrogen, which fell in Group 1.
- Halogens – These elements represent one of two subsets of the nonmetals and are chemically reactive.
- Noble Gases – These are colorless, odorless and almost completely nonreactive elements.
READ ALSO: STATES OF MATTER – The Three States And Examples
