【】NH3 Lewis Structure , Valence Electrons ,Formal Charge,Polar or Non Polar,Octet Rule

NH3 Lewis Structure

Answer:

NH3 Lewis structure ( ammonia electron dot structure) is that type of diagram where we show the total eight valence electrons of NH3 as dots , or dots and dashes(-).

                             NH3 Lewis Structure

In Lewis structure,it is common that a bonding pair of two electrons can be shown by dash(-) or dots(●●) but a lone pair of two electrons is shown by dots[●●].

In NH3,all hydrogens follows the duet rule and the nitrogen atom follows the octet rule.

In NH3 Lewis structure,we get four pairs of electrons.Out of four pairs of electrons,NH3 has three bond pairs and one lone pairs of electrons.

Explanation:

Hello,today I am going to draw the NH3 Lewis  structure  in just few steps.

 Step-1:NH3 Valence Electrons

To draw the NH3 Lewis  structure , we have to find out the NH3 total valence electrons first.We express valence electrons as dots in lewis dot structure.

To get the valence electrons of nitrogen,we need to look at the electronic configuration of nitrogen.



N(7)=1s²2s²2p³



The highest value of principal quantum number  here is n=2.


The highest value of principal quantum number ,n , indicates the valence shell and we know the electrons in valence shell is called valence shell.




The nunber of valence electrons in nitrogen is 5.


Again, we have to find out the valence electrons of hydrogen,H.

To get the valence electrons of hydrogen,we need to look at the electronic configuration of hydrogen.


H(1)=1s¹

The highest value of principal quantum number here is n=1.

The highest value of principal quantum number ,n , indicates the valence shell and we know the electrons in valence shell is called valence shell.




The nunber of valence electrons in hydrogen is 1.

Now we have to count total number of valence electrons for NH3.


N =5

3×H=1×3=3


So,the total number of  NH3 valence electrons is eight ( 5+3=8 ).

Here is the another way of finding NH3 valence electrons.

Nitrogen is an element of group 5A,so it has five valence electrons.Besides,hydrogen is an element of group 1A,so it has one valence electron.

For NH3,

N --->5

H --->1 ×3 =3

------------------

NH3 = 8 valence electrons

             NH3 Lewis  structure  Setup Step-2:

Now we have to determine the central atom in NH₃.The central atom is that kind of atom that is single or that has lower electronegativity.In case of NH₃,N is the central atom and H is the outer atom.Remember that hydrogen is always the outer atom.




          NH3 Lewis  structure  Setup Step-3:

Now we need to connect the outer atoms with  the central atoms using dots  or line(-) which are called bonds.

Every line represent two 【●●】dots or two valence electrons.

Or,

In the above structure,we have used 6 valence electrons.So,we have 8-6=2 left.


Now we will use these 2 valence electrons to satisfy the octet  for central atom.

NH3 Lewis structure

Or,

The above structure is the NH3 Lewis structure.

In NH3,all hydrogens follows the duet rule and the nitrogen atom follows the octet rule.

NH3 Lewis Structure:Formal Charge

Now we can calculate the formal charge of all atoms of NH3 using the formula for formal charge.

Formula-1:

Formula-2:

Formula-3:

Formal Charge=Valence Electrons-Dots-Lines

H --->1-0-1 =0

N------>5 - 2 -3 =0

All the hydrogens have the same electronic environment.So,their formal charge will be the same.

The formal charge of all H is zero in NH3.Besides,the formal charge of N in NH3 is also zero.

Formula-4:

Here is the formula for determining the formal charge of each atom in NH3 Lewis structure.

•Formal charge =Valence electrons - Unshared Electrons - 1/2(Shared Electrons)

•Valence electrons of N  =5

•Shared electrons of N= 6

•Unshared electrons of N = 2

●F.C. of N   =5- 2 -1/2(6)

                  =5-2-3

                 =5- 5

                   =0 

●•Valence electrons of H  =1

•Shared electrons of H= 2

•Unshared electrons of H= 0

●F.C. of H   =1- 0 -1/2(2)

                  =1-0-1

                 =1- 1

                   =0 

All the hydrogens have the same electronic environment.So,their formal charge will be the same.

Continue

Questions and Answers

Is NH3 Lewis Structure Polar or Non Polar?

Answer:

Every N-H bond in NH3 is polar because nitrogen is more electronegative than hydrogen.Thus every N-H bond has dipole moment.Due to   asymmetrical shape of NH3,the net dipole moment or molecular dipole moment of NH3 molecule is not zero.This indicates that NH3 is polar.

Does NH3 follow or obey the octet rule?

Answer:

Yes,in the best Lewis structure of NH3,the nitrogen atom,N, in NH3 follows/obeys the octet rule and the hydrogen atoms follow the duet rule .

In explanation,I will say that nitrogen is a nonmetal and hydrogen is also a nonmetal.So,all atoms in NH3 will share electrons in such a way that all atoms can achieve eight valence electrons or duet valence elctrons in their valence shells and thus can gain more stability.

In NH3 ,the nitrogen atom has shared two electrons with each Hydrogen and each hydrogen has shared two electrons with the nitrogen atom.

By sharing ,the N atom in NH3, has achieved the eight valence electrons in its most occupied energy levels, and each hydrogen has achieved two valence electrons, So NH3 follows/obeys the octet rule or duet rule.

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