Question

How do identify meatal and non meatal.

Answer 1

Mark me brainlist please.

My easy and helpful identification

For metal and non metal is that

Valency of elements 1 to 3 is metals

While valency 5 to 7 is non metal

So please mark me brainlist

Answer 2

✌hey here is ur ans ..✌✌


It's quite simple

We know

Atomic no =no of proton=no of eletron

So by Atomic no we are able to identify no of elctron.

Simply arrange the electron in a shell .

If it gains electron from others then it is electronegative (Non Metal).

Similarly if it loses electron then it is electropositive (Metal).

All I want to say is Electropositive elements are metal whereas electronegative elements are non metal.

Have a look here

SOME basics

The process of filling 2 electron in 1st shell is duplet and the process of filling 8 elctrons in 3rd shell 4th shell And so on is called Octet .

Simply

For very elements

1st shell contains 2 elctrons

And further on shell consist 8 elctrons

Sodium

Atomic no=11

No of eletron=11

Arranging them in shell we get

1st shell = 2 electron

2nd shell = 8 electrons

3rd shell = 1 electron

To be octet sodium has to gain seven electron which is not suitable.

So sodium loses it 1 electron to be stable

Since sodium loses elctron to be stable so it is Electropositive (Metal).

Note :Atom only can gain and lose four electrons (For example in the case of sodium , sodium can't gain seven elctron but it can loses one elctron).

Similarly in the case of chlorine

Atomic no of chlorine =17

No of eletron =17

1st shell = 2 electrons

2nd shell =8 electrons

3rd shell = 7 electrons

As I told you elements only can gain four electrons and lose four electrons.

Let us suppose chlorine loses four elctron then 3 electrons are still left (Octet rule is not obeyed) but if chlorine gains 1 elctron then it's 3rd shell becomes Octet .and chlorine is now stable .

As a result chlorine gains one elctron to be stable so it is electronegative (Non metal) .

So chlorine is non metal.

OTHER METHOD

Other method to identify Metal by Atomic no

This method is limited Up to Hydrogen to calcium only.

In periodic table

The horizontal row is called periods.

The vertical column are called group.

In modern periodic table there are total seven periods and eighteen groups.

Elements underGroup no 1,2 and 3 are metals (counting from left to right). Here Hydrogen is an exception.

Elements under Group no 4 is metalloid s(counting from left to right).

Elements under Group no 5,6and 7 are no metals (counting from left to right).

First we have to know how to identify group no (Only from Hydrogen to calcium this is applicable).

For example group no of sodium

Group no of elements = no of valence electrons

The outermost orbit is called valence shell and the electron present in valence shell is called valence electrons.

Sodium

1st shell =2 electron

2nd shell =8 electrons

3rd shell = 1 electron

The outermost shell is 3rd shell so it is called valence shell of sodium and it contains 1 elctron so it's valence elctron is 1.

Group no =no of valence electrons

Therefore group no is 1

As I told you above

The elements comes under Group no 1,2and 3 are metals so sodium is metal .

Similarly

Chlorine

1st shell =2 electrons

2nd shell=8 electrons

3rd shell =7 electrons

The outermost shell is third shell so it is called valence shell of chlorine and it contains 7electrons so it's valence electrons is 7.

Group no =No of valence electrons

Therefore group no is 7

As I told you above the elements under Group no 7 are non metals .

So chlorine is non metal.

hope it will help uh ..☺☺