Ready to learn how to draw the lewis structure of SiH2O?
Awesome!
Here, I have explained 6 simple steps to draw the lewis dot structure of SiH2O (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 SiH2O contains a double bond between the Silicon (Si) & Oxygen (O) atom and two single bonds between Silicon (Si) & Hydrogen (H) atoms. The Silicon atom (Si) is at the center and it is surrounded by two Hydrogen (H) and one Oxygen atom (O). The Oxygen atom has 2 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 SiH2O).
6 Steps to Draw the Lewis Structure of SiH2O
Step #1: Calculate the total number of valence electrons
Here, the given molecule is SiH2O. In order to draw the lewis structure of SiH2O, first of all you have to find the total number of valence electrons present in the SiH2O 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 SiH2O
- For Silicon:
Silicon is a group 14 element on the periodic table.
Hence, the valence electrons present in silicon is 4 (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).
- For Oxygen:
Oxygen is a group 16 element on the periodic table.
Hence, the valence electron present in oxygen is 6 (see below image).
Hence in a SiH2O molecule,
Valence electrons given by Silicon (Si) atom = 4
Valence electron given by each Hydrogen (H) atom = 1
Valence electrons given by Oxygen (O) atom = 6
So, total number of Valence electrons in SiH2O molecule = 4 + 1(2) + 6 = 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). [1]
Here in the SiH2O molecule, if we compare the silicon atom (Si) and oxygen atom (O), then the silicon is less electronegative than oxygen.
So, silicon should be placed in the center and the oxygen atom will surround it.
Also as per the rule, we have to keep hydrogen outside.
Step #3: Put two electrons between the atoms to represent a chemical bond
Now in the above sketch of SiH2O molecule, put the two electrons (i.e electron pair) between the silicon-oxygen atoms and silicon-hydrogen atoms to represent a chemical bond between them.
These pairs of electrons present between the Silicon & Oxygen atoms as well as between the Silicon & Hydrogen atoms form a chemical bond, which bonds these atoms with each other in a SiH2O 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 SiH2O, the outer atoms are hydrogen atoms and oxygen 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).
You also have to see whether the oxygen atom is forming an octet or not! (because oxygen requires 8 electrons to have a complete outer shell).
You can see in the above image that both the hydrogen atoms form a duplet. And the oxygen atom also forms an octet.
Also, all the 12 valence electrons of SiH2O molecule (as calculated in step #1) are used in the above structure. So there are no remaining electron pairs.
Hence there is no change in the above sketch of SiH2O.
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 move the electron pair from the outer atom to form a double bond or triple bond
In this step, we have to check whether the central atom (i.e silicon) has an octet or not.
In simple words, we have to check whether the central Silicon (Si) atom has 8 electrons or not.
As you can see from the above image, the central atom (i.e silicon) has only 6 electrons. So it does not fulfill the octet rule.
Now, in order to fulfill the octet of a silicon atom, we have to move the electron pair from the outer atom (i.e oxygen atom) to form a double bond.
Now you can see from the above image that the central atom (i.e silicon), is having 8 electrons. So it fulfills the octet rule.
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 silicon atom (Si), oxygen (O) atom 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 Silicon:
Valence electrons = 4 (as it is in group 14)
Nonbonding electrons = 0
Bonding electrons = 8 - For Hydrogen:
Valence electron = 1 (as it is in group 1)
Nonbonding electrons = 0
Bonding electrons = 2 - For Oxygen:
Valence electron = 6 (as it is in group 16)
Nonbonding electrons = 4
Bonding electrons = 4
Formal charge | = | Valence electrons | – | Nonbonding electrons | – | (Bonding electrons)/2 | ||
Si | = | 4 | – | 0 | – | 8/2 | = | 0 |
H | = | 1 | – | 0 | – | 2/2 | = | 0 |
O | = | 6 | – | 4 | – | 4/2 | = | 0 |
So you can see above that the formal charges on silicon, oxygen as well as hydrogen are “zero”.
Hence, there will not be any change in the above structure and the above lewis structure of SiH2O is the final stable structure only.
Each electron pair (:) in the lewis dot structure of SiH2O represents the single bond ( | ). So the above lewis dot structure of SiH2O can also be represented as shown below.
Related lewis structures for your practice:
Lewis Structure of OF3-
Lewis Structure of PH4+
Lewis Structure of SHF
Lewis Structure of SeS3
Lewis Structure of IBr5
Article by;
Jay is an educator and has helped more than 100,000 students in their studies by providing simple and easy explanations on different science-related topics. With a desire to make learning accessible for everyone, he founded Knords Learning, an online learning platform that provides students with easily understandable explanations.
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