# Question #78d26

Mar 20, 2017

My thoughts are offered below. I hope others will join in...

#### Explanation:

I'm not quite certain how to frame this question, but here goes!

To my knowledge, there is no such thing as ${H}_{4} {O}_{2}$. When we write the symbols of the elements together this way, we are implying that all the atoms in the formula are bonded into a single molecule.

On that basis, this formula would not represent a molecule that I know of.

If we meant for this to be two water molecules, it should be written $2 {H}_{2} O$, so that the coefficient in front of the formula tells us these are two separate, but identical particles.

Mar 20, 2017

It will be a completely different molecule.

#### Explanation:

To answer this, you'll need a basic understanding of the Lewis structure and how the Octet Rule works.

This is how a water molecule (${H}_{2} O$) looks like if you draw its Lewis structure. Notice that in order to follow the Octet Rule, the $O$ atom has to create a SINGLE bond with each of the $H$ atoms.

That is, the $O$ atom with six electrons on its outer shell ended up sharing two of its electrons with two $H$ atoms equally.

As result of the covalent bonding, the $O$ atom now has eight valence electrons (resembling the stability of noble gasses) while the $H$ atom has two valence electrons (resembling the stability of $H e$).

The formula ${H}_{4} {O}_{2}$, on the other hand, should not exist as it will violate the octet rule. At best, this formula represents a hydrate of a water molecule and should be written like this:

${H}_{2} O$ $\cdot$ ${H}_{2} O$ (attracted by weak intermolecular force)