13 Formal Charge Example: Detailed Explanations

In this article we will discuss about formal charge example

Starts with examples to find out formal charge of molecule,

1. O3

The structure of this , In which 3 oxygen atom will appear, by their different lewis structure. oxygen has 8 atomic number and 16 mass number. This is the ozone molecule. this is an allotrope of oxygen. ozone formed by the dioxygen molecule when come to contact with UV light.

Oxygen having 6 valence electron .

# The charge of the Atom O(1) will be
=6-2-3

=6-5

=1

(it will be +1)

# The charge of the atom O(2):

=6-4-2

=0

# The charge of the atom O(3):

=6-6-1

=-1

2: H2O MOLECULE

The structure of this :

formal charge example
Image credit : water from istock

It contain 2 hydrogen atom and 1 oxygen atom in their structure. It is tasteless and transparent by its behavior. Here oxygen having 6 valence electron and hydrogen having 1 atomic number.

# oxygen in water molecule contain

=6-4-2

=0

# of H(1)

=1-0-1

=0

# hydrogen in water molecule contain charge of H(2)

=1-0-1

=0

3: CO2 MOLECULE

co2
Image credit : Carbon dioxide from istock

Carbon dioxide is contain 1 carbon and 2 oxygen molecule covalently bonded with each other. Carbon having valence electron 4 ,0 lone pair electron and 4 bonds around it.

The charge of C in carbon dioxide = 4-0-4=0

Oxygen having 6 valence electron ,4 dots and 2 bond pair .

The charge of carbon dioxide of O=6-4-2=6-6=0

So charge of whole molecule is 0.

4.BH4 MOLECULE

 3 and 1 are the valence e of boron and hydrogen ,by putting the formula,

Formal charge of B= 3-0-4=-1

Formal charge of H=1-0-1=0

The whole charge of molecule will be =-1

5.CH3+ MOLECULE

It contains one carbon and three hydrogen atom .methylium cation has geometry structure is trigonal planner and bond angle is 120 degree . This is a methyl group alkyl derived from it. The 4 and 1 are the valence electron of carbon and hydrogen .

Charge of C in this molecule=4-0-3=1

Charge of H in this molecule=1-0-1=0

Whole charge of the molecule is +1 .

6.NH3 MOLECULE

In this nitrogen having 5 valence e,2 dots and 3 . Nitrogen covalently bonded with 3 hydrogen atom and 1pair of electrons are present here

istockphoto 172943522 1024x1024 1
Image credit: ammonia by istock

The charge of nitrogen in this molecule=5-2-3=0

The charge of hydrogen in this molecule is 0.

So the whole charge will be 0.

7.SCN Molecule

 Starts with carbon ,we seen that carbon atom shares 4 bond pairs . so the charge of C is 0 (4-0-4=0)

After that we seen that sulfur atom shares 1 bond pair ,3 lone pair and 6 valence e.

The charge of sulfur= 6-6-1=-1

Next we observe nitrogen share 3 bond pair,1 lone pair and has total 5 valence electron.

The charge of N =5-2-3=0

The whole charge will be -1.

8.N2O MOLECULE

This is known as laughing gas , so the structure of this :

We know nitrogen has 5 valence electrons and oxygen have 6 valence electrons.

By calculating the charge of each of the atom :

The charge of N1 in molecule=5-4-2=-1

The charge of N2 in molecule=5-0-4=1

The charge of Oxygen=6-4-2=0

Whole charge will be zero.

9: CO MOLECULE

Lets calculate formal charge for each atom in the carbon monoxide molecule

Here carbon contain 4 valence electron, , two lone pair electron , 3 bonds around it.

istockphoto 533180239 612x612 1
Image credit: carbon monoxide from istock

.Formal charge of C =4-2-3=-1

Oxygen having  6 valence electron , 2 lone pair electron , 3 number of bonds around it.

Formal charge of O=6-2-3=+1

10: H3O+ MOLECULE

Oxygen having 8 valence electrons in their valence shell.

Formal charge of O=6-2-3=+1

Formal charge of H=1-0-1= 0

11:NH4+ MOLECULE

Nitrogen has 5 valence electron , 4 bond pair ,0 lone pair electron here.Hydrogen has 1 valence electron and only 1 bond present around it.

Formal charge of N = 5-0-4=+1

Formal charge of H=1-0-1=0

Read more on: Peptide Bond vs Ester Bond: Comparative Analysis And Facts

12: CH4 MOLECULE

Carbon has 4 and hydrogen has 1 valence electron.

Formal charge of carbon= 4-0-4=0

Formal charge of of hydrogen=1-0-1=0

13:H3O+ MOLECULE

Oxygen having 6 valence electron, two dots and 3 bonds around it.

Formal charge of O=6-2-3=1

Formal charge of H =1-0-1=0

14.BH3 MOLECULE

Boron having 3 valence electron .

Formal charge of boron =3-0-3=0

Formal charge of hydrogen=1-0-1=0