Periodic table box

In this les­son, we will tell you about the in­for­ma­tion on each el­e­ment that you can find in the pe­ri­od­ic ta­ble.

Let's click on an el­e­ment, for ex­am­ple, sul­fur. You see the square, where sul­fur is? This is the sym­bol of the el­e­ment.

This is the name of the el­e­ment. Sul­fur. This is the atom­ic num­ber of sul­fur. 16. It shows the num­ber of pro­tons in the nu­cle­us of a sul­fur atom.

Ques­tion: how many elec­trons are there in a sul­fur atom?

Yes. The num­ber of elec­trons in an atom is equal to the num­ber of pro­tons in the nu­cle­us of the atom.

This is the av­er­age atom­ic mass of the sul­fur atom. It is the weight­ed av­er­age mass of the iso­topes of sul­fur in a nat­u­ral­ly oc­cur­ring sam­ple of sul­fur.

In the les­son "atom­ic mass" we will show you how to cal­cu­late it.

Now, look at the right pan­el.

Here you see the elec­tron con­fig­u­ra­tion of the sul­fur atom. It is also shown in the bot­tom of the square in short form.

Look at it care­ful­ly.

Sul­fur has two elec­trons in the 1s or­bital, two elec­trons in the 2s or­bital, six elec­trons in the 2p or­bital, two elec­trons in the 3s or­bital and four elec­trons in the 3p or­bital.

So, we have one s two, two s two, two p six, three s two, three p four.

The sum of su­per­scripts equals the num­ber of elec­trons in the atom.

For sul­fur it is 16.

Some­times we can write the elec­tron con­fig­u­ra­tion in short­hand. For sul­fur it looks like this.

Neon in brack­ets means that sul­fur has filled first and sec­ond lev­els, like the neon atom has. Also sul­fur has 2 elec­trons in the 3s or­bital and four elec­trons in the 3p or­bital.

So, we write Neon in square brack­ets, and af­ter that write three s two, three p four.

Now, you see, that sul­fur has 6 va­lence elec­trons. This is the main in­for­ma­tion about the el­e­ment that you can find in the pe­ri­od­ic ta­ble.

Also, the col­or of the square in dif­fer­ent ta­bles usu­al­ly means some­thing. In our ta­ble, the pale blue col­or of sul­fur square means, that sul­fur is a non­metal.

Let's take an­oth­er el­e­ment, for ex­am­ple, oxy­gen.

How many pro­tons does oxy­gen have? Yes, an oxy­gen atom has 8 pro­tons.

How many elec­trons does oxy­gen have? You are right. In an atom, the num­ber of elec­trons is equal to the num­ber of pro­tons.

How many va­lence elec­trons does oxy­gen have?

Valenсe elec­trons are the elec­trons lo­cat­ed on the out­er elec­tron shell of an atom. There are 2 elec­trons on the 2s or­bital and 4 elec­trons on the 2p or­bital. So, the oxy­gen atom has six va­lence elec­trons.

Now if you want to know some in­for­ma­tion about oth­er el­e­ments, you should go to the Lab Pe­ri­od­ic ta­ble.