What is the Charge on H2O (Water)? And Why?

The Charge of H2O (Water) is 0.

But the question is how can you say that the charge on H2O (Water) is 0?

Well you can say this by calculating its formal charge.

So let’s calculate the formal charge of H2O (Water).

If you are a visual learner like me, then here is a short two minute video for you.

Calculating the formal charge of H2O using lewis structure

In order to calculate the formal charge on H2O (Water), you should know the Lewis dot structure of H2O (Water).

Here is the lewis structure of H2O.

Now using the above lewis structure of H2O, you have to find the formal charge on each atom that is present in the H2O molecule.

For calculating the formal charge, you need to remember this formula;

Formal charge = Valence electrons – Nonbonding electrons – (Bonding electrons)/2

You can see the bonding and nonbonding electrons of H2O from the image given below.

So now let’s calculate the formal charge on each individual atom present in H2O.

Formal charge on Hydrogen atom:
Valence electron = 1 (as it is in group 1 on periodic table) ^[1]
Nonbonding electrons = 0
Bonding electrons = 2

So according to the formula of formal charge, you will get;

Formal charge on Hydrogen = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 1 – 0 – (2/2) = 0

So the formal charge on hydrogen atom is 0.

Formal charge on Oxygen atom:
Valence electrons = 6 (as it is in group 16 on periodic table) ^[2]
Nonbonding electrons = 4
Bonding electrons = 4

So according to the formula of formal charge, you will get;

Formal charge on Oxygen = Valence electrons – Nonbonding electrons – (Bonding electrons)/2 = 6 – 4 – (4/2) = 0

So the formal charge on oxygen atom is 0.

Now you can see that all the atoms of H2O have 0 formal charge. 

This indicates that the overall H2O (Water) molecule also has 0 charge and hence it is a neutral molecule.

I hope you have understood the above calculations for the formal charge of H2O (Water). 

Check out some other related topics for your practice.

Related topics:
Charge on ClO4 (Perchlorate ion)
Charge of Manganese (Mn)
Charge of Strontium (Sr)
Charge of Boron (B)
Charge of Tin (Sn)