How Many Valence Electrons Does Hydrogen Have? Now I am going to show you how many valence electrons hydrogen have in just 5 steps. Step-1: First, find the atomic number of hydrogen from periodic table. Hydrogen has only one valence electron and can form only one bond with an atom that has an incomplete outer shell. Chlorine has seven valence electrons and can form only one bond with an atom that donates a valence electron to complete chlorine's outer shell.

The Number Of Valence Electrons In Hydrogen

here is an EASY way, and a FORMAL way to draw the Lewis structure of HCN, Hydrogen cyanide:


Valence

Formal Way

In the formal way we find how many electrons we have (step 1), how many each atom needs (step 2), how many of those are bonding (step 3 & 4), and how many are lone pairs (step 5). This info can then be used to determine the Lewis Dot Structure.

Step 1: Find valence e- for all atoms. Add them together.

H: 1
C: 4
N: 5

Total=10

Step 2: Find octet e- for each atom and add them together.

H: 2
C: 8
N: 8

Number Of Valence Electrons Present In Hydrogen Atom

Total=18

Step 3: Find the bonding e-. Subtract step 1 total from step 2

18-10=8e-

Step 4: Find number of bonds by dividing the number of bonding electrons by
2 (because each bond is made of 2 e-)

8e-/2 = 4 bonds

Step 5: The rest are nonbonding pairs. Subtract bonding electrons (step 3) from valence electrons (step 1).

10-8= 2e-= 1 lone pair

Use information from step 4 and 5 to draw the HCNLewis structure.

How Many Valence Electrons Are In Hydrogen

Easy Way – Treat them like Puzzle Pieces

Lewis structure of HCN

Number Of Valence Electrons In Hydrogen Sulfide

Alternatively a dot method can be used to draw the HCN Lewis structure.

Calculate the total valence electrons in the molecule.

H: 1
C: 4
N: 5

Total=10

Remember, uncharged carbon likes to have four bonds and no lone pairs. Uncharged nitrogen has three bonds and one lone pair. Hydrogen has one bond and no lone pairs.

Put carbon in the center and arrange hydrogen and nitrogen atoms on the sides. Arrange electrons until both carbon and nitrogen get a triple bond (giving an octet) and hydrogen has 2. This will put a lone pair on nitrogen.

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A brief closing summary: The Lewis structure is used to represent bonding in a molecule, whether that be covalent or ionic. Covalent bonds are formed by sharing electrons between the atoms and are stronger than ionic bonds, which are much more of an electrostatic interactions. Most Lewis structures you encounter will be covalent bonds. Most Lewis structures will follow the octet rule, which states that the outer (valence) shell is stable when it has eight electrons. There are MANY exceptions to this rule, but it should be used as a general guide for creating Lewis structures.