Hello, my dear little viewer! How do you do?
This is the Periodic Table of chemical Elements.
I am sure you are familiar with this table, unless you have been living in a cave until yesterday.
But I will give you, my Neanderthal viewer, a few information..
..about the Periodic Table of the Elements.
All known chemical elements have been placed in this table..
..and are grouped horizontally..
..and vertically.
Horizontal lines are called Periods..
..and vertical lines are called Groups.
Elements in the same Period distribute their electrons in the same number of shells.
For example, all elements of 4th Period contain 4 shells of electrons.
Elements in the same Group of Periodic Table have similar chemical properties..
..and have the same number of electrons in their outer shell.
For example, all elements of Group 2 have oxidation state +2..
..and 2 electrons in their outer shell.
The 1st Group of the Periodic Table is called Alkali metals
Some other Groups of the Periodic Table are Alkaline Earth metals, right next to Alkali metals..
Halogens in Group 17..
..and Noble Gases in Group 18.
Also, the Periodic Table is divided to blocks..
..depending on the subshell where the last electron is placed.
Subshells are spaces inside shells.
So, there is s block..
..p block, d block..
..f block..
..block for notes..
..and block and delete, which you will press if I continue this bad jokes.
Don't even think about it!
In other words, the Periodic Table is a picture of electron configuration of chemical elements..
..which defines all their chemical and physical properties.
The current Periodic Table was created by Russian chemist, Dmitri Mendeleev..
..who is well known by everyone, even by my grandmother!
- Grandma, do you know Dmitri Mendeleev?
- I know him. I saw him yesterday at church!
- We had a little chat!
Anyway, Mendeleev's Periodic Table is not the only Periodic Table that exists.
French engineer, Charles Janet created a very interesting Periodic Table in 1929.
In 1975, the Spanish physicist Albert Tarantola proposed this same Periodic Table.
He thought that he had discovered it while he studied at the University.
Blocks s, p, d and f form steps in this Periodic Table..
..so it is easier to represent electron configuration into orbitals.
Also, Lanthanides and Actinides are part of the Periodic Table..
..and are not placed outside it, as if they have pissed in a well (Greek expression).
In conclusion, Janet and Tarantola's Periodic Table is more symmetrical than Mendeleev's..
..and more attractive.
Ok, I just made a compliment to the Periodic Table.
Sometimes, even a Periodic Table needs its applause!
A disadvantage this Periodic Table has is that each Period begins and ends a bit disorderly.
This is the 1st Period..
..this is the 2nd Period..
..this is the 3rd Period and so on.
But why are there more than one Periodic Tables, for example, this..
..this..
..this..
..and this?
The truth is that Mendeleev's Periodic Table has some cons.
For example, elements of Zinc Group behave more like Alkaline Earth metals..
..that's why they shouldn't be put in d block's Transition metals.
Elements Lutetium and Lawrencium shouldn't be placed at the end of Lanthanides and Actinides..
..but right next to Lanthanium and Actinium instead.
Hydrogen behaves more like a pseudohalogen..
..so it's not correct placing it above Alkali metals.
Helium should be placed above Beryllium..
..because it belongs to s block, not p block.
Also, it should be named Helion, not Helium..
..because the ending "-ium" is used for metals.
Anyway, Mendeleev's Periodic Table is the most practical..
..that's why you will only be taught about this Periodic Table during your school years.
I am sure that your life and mine would be much better if the Periodic Table of Elements was like this.
I am Dimitris! See you in the next video!
