Ready to learn how to draw the lewis structure of SnCl2?
Here, I have explained 6 simple steps to draw the lewis dot structure of SnCl2 (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 SnCl2 contains two single bonds between the Tin (Sn) atom and each Chlorine (Cl) atom. The Tin atom (Sn) is at the center and it is surrounded by 2 Chlorine atoms (Cl). The Tin atom has 1 lone pair while both the Chlorine atoms have 3 lone pairs.
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 SnCl2).
5 Steps to Draw the Lewis Structure of SnCl2
Step #1: Calculate the total number of valence electrons
Here, the given molecule is SnCl2. In order to draw the lewis structure of SnCl2, first of all you have to find the total number of valence electrons present in the SnCl2 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 SnCl2
- For Tin:
Tin is a group 14 element on the periodic table.
Hence, the valence electron present in tin is 4 (see below image).
- For Chlorine:
Chlorine is a group 17 element on the periodic table.
Hence, the valence electron present in chlorine is 7 (see below image).
Hence in a SnCl2 molecule,
Valence electrons given by Tin (Sn) atom = 4
Valence electrons given by each Chlorine (Cl) atom = 7
So, total number of Valence electrons in SnCl2 molecule = 4 + 7(2) = 18
Step #2: Select the center atom
While selecting the 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 SnCl2 molecule, if we compare the tin atom (Sn) and chlorine atom (Cl), then the tin is less electronegative than chlorine.
So, tin should be placed in the center and the remaining 2 chlorine atoms will surround it.
Step #3: Put two electrons between the atoms to represent a chemical bond
Now in the above sketch of SnCl2 molecule, put the two electrons (i.e electron pair) between the tin atom and chlorine atom to represent a chemical bond between them.
These pairs of electrons present between the Tin (Sn) and Chlorine (Cl) atoms form a chemical bond, which bonds the tin and chlorine atoms with each other in a SnCl2 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 SnCl2, the outer atoms are chlorine atoms.
So now, you have to complete the octet on these chlorine atoms (because chlorine requires 8 electrons to have a complete outer shell).
Now, you can see in the above image that both the chlorine atoms form an octet.
Also, only 16 valence electrons of SnCl2 molecule are used in the above structure.
But there are total 18 valence electrons in SnCl2 molecule (as calculated in step #1).
So the number of electrons left to be kept on the central atom = 18 – 16 = 2.
So let’s keep these two electrons (i.e 1 electron pair) on the central atom.
Now, let’s move to the next step.
Step #5: 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 tin atom (Sn) as well as each chlorine atom (Cl).
For that, you need to remember the formula of formal charge;
Formal charge = Valence electrons – Nonbonding electrons – (Bonding electrons)/2
- For Tin:
Valence electron = 4 (as it is in group 14)
Nonbonding electrons = 2
Bonding electrons = 4
- For Chlorine:
Valence electron = 7 (as it is in group 17)
Nonbonding electrons = 6
Bonding electrons = 2
|Formal charge||=||Valence electrons||–||Nonbonding electrons||–||(Bonding electrons)/2|
So you can see above that the formal charges on tin as well as chlorine are “zero”.
Hence, there will not be any change in the above structure and the above lewis structure of SnCl2 is the final stable structure only.
Each electron pair (:) in the lewis dot structure of SnCl2 represents the single bond ( | ). So the above lewis dot structure of SnCl2 can also be represented as shown below.