Ready to learn how to draw the lewis structure of N2H2?
Here, I have explained 6 simple steps to draw the lewis dot structure of N2H2 (along with images).
So, if you are ready to go with these 6 simple steps, then let’s dive right into it!
Lewis structure of N2H2 contains one double bond between the two Nitrogen (N) atoms and two single bonds between Nitrogen (N) & Hydrogen (H) atoms. Both the nitrogen atoms have one lone pair.
Let’s draw and understand this lewis dot structure step by step.
(Note: Take a pen and paper with you and try to draw this lewis structure along with me. I am sure you will definitely learn how to draw lewis structure of N2H2).
6 Steps to Draw the Lewis Structure of N2H2
Step #1: Calculate the total number of valence electrons
Here, the given molecule is N2H2 (or Dinitrogen dihydride). In order to draw the lewis structure of N2H2, first of all you have to find the total number of valence electrons present in the N2H2 molecule.
(Valence electrons are the number of electrons present in the outermost shell of an atom).
So, let’s calculate this first.
Calculation of valence electrons in N2H2
- For Nitrogen:
Nitrogen is a group 15 element on the periodic table.
Hence, the valence electrons present in nitrogen is 5 (see below image).
- For Hydrogen:
Hydrogen is a group 1 element on the periodic table.
Hence, the valence electron present in hydrogen is 1 (see below image).
Hence in a N2H2 molecule,
Valence electrons given by each Nitrogen (N) atom = 5
Valence electron given by each Hydrogen (H) atom = 1
So, total number of Valence electrons in N2H2 molecule = 5(2) + 1(2) = 12
Step #2: Select the center atom (H is always outside)
While selecting the center atom, always put the least electronegative atom at the center.
(Remember: Fluorine is the most electronegative element on the periodic table and the electronegativity decreases as we move right to left in the periodic table as well as top to bottom in the periodic table).
Here in the N2H2 molecule, if we compare the nitrogen atom (N) and hydrogen atom (H), then hydrogen is less electronegative than nitrogen. But as per the rule, we have to keep hydrogen outside.
So, both the nitrogen atoms should be placed in the center and the remaining 2 hydrogen atoms will surround it.
Step #3: Put two electrons between the atoms to represent a chemical bond
Now in the above sketch of N2H2 molecule, put the two electrons (i.e electron pair) between the nitrogen-nitrogen atoms and nitrogen-hydrogen atoms to represent a chemical bond between them.
These pairs of electrons present between the Nitrogen atoms as well as between the Nitrogen and Hydrogen atoms form a chemical bond, which bonds these atoms with each other in a N2H2 molecule.
Step #4: Complete the octet (or duplet) on outside atoms. If the valence electrons are left, then put the valence electrons pair on the central atom
Don’t worry, I’ll explain!
In the Lewis structure of N2H2, the outer atoms are hydrogen atoms as well as a nitrogen atom.
So now, you have to check whether these hydrogen atoms are forming a duplet or not! (because hydrogen requires only 2 electrons to have a complete outer shell).
Also, the outer nitrogen atom forms an octet.
You can see in the above image that both the hydrogen atoms form a duplet and a nitrogen atom also forms an octet.
Also, only 10 valence electrons of N2H2 molecule are used in the above structure.
But there are total 12 valence electrons in N2H2 molecule (as calculated in step #1).
So the number of electrons left to be kept on the central nitrogen atoms = 12 – 10 = 2.
So let’s keep these two electrons (i.e 1 electron pair) on the central nitrogen atom.
Now, let’s move to the next step.
Step #5: Check whether the central atom has octet or not. If it does not have an octet, then convert the lone pair into double bond or triple bond
In this step, we have to check whether the central atoms (i.e two nitrogen atoms) have an octet or not.
In simple words, we have to check whether the central Nitrogen (N) atoms has 8 electrons or not.
As you can see from the above image, one of the nitrogen atoms has only 6 electrons. So it does not fulfill the octet rule.
Now, in order to fulfill the octet of this nitrogen atom, we have to convert the lone pair into a double bond.
Now you can see from the above image that both the central nitrogen atoms are having 8 electrons. So they fulfill the octet rule and both the nitrogen atoms are stable.
Step #6: Final step – Check the stability of lewis structure by calculating the formal charge on each atom
Now, you have come to the final step and here you have to check the formal charge on nitrogen atoms (N) as well as hydrogen atoms (H).
For that, you need to remember the formula of formal charge;
Formal charge = Valence electrons – Nonbonding electrons – (Bonding electrons)/2
- For Nitrogen:
Valence electrons = 5 (as it is in group 15)
Nonbonding electrons = 2
Bonding electrons = 6
- For Hydrogen:
Valence electron = 1 (as it is in group 1)
Nonbonding electrons = 0
Bonding electrons = 2
|Formal charge||=||Valence electrons||–||Nonbonding electrons||–||(Bonding electrons)/2|
So you can see above that the formal charges on nitrogen as well as hydrogen are “zero”.
Hence, there will not be any change in the above structure and the above lewis structure of N2H2 is the final stable structure only.
Each electron pair (:) in the lewis dot structure of N2H2 represents the single bond ( | ). So the above lewis dot structure of N2H2 can also be represented as shown below.