Why is water (H2O) a polar molecule?

To understand why water is a polar molecule, we need to understand a few key concepts about polarity. First, it we look at the Lewis structure for water. this helps understand the molecular geometry of the water molecule which is bent.

Because H2O has a bent molecular geometry it has a side with the O atom and a side with the H atoms. The electrons in the covalent bond between the O and H atoms aren’t shared equally. They spend more time around the O than with the H atoms. And because electrons are negative, the O becomes a bit more negative. That means the H atoms are more positive. We have poles. So water is a polar molecule.

We can check the EN values on this Periodic Table. Oxygen has a value of 3.5. Hydrogen is further away and is 2.1. So the the electrons in the bond between the O atom and the H atoms will spend more time around the O atom.

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[camryntrapp]

This video allowed me to understand electronegativity and polarity mere hours before my chemistry exam. thank you.

[ameera]

this is the clearest explanation i watched

[pavlovafrogs]

Amazing explanation with very helpful visuals! Thank you!

[pepesito]

you're RIDICULOUS. that little 3d bit with the jiggle physics? AWESOME. keep it up!

[kreed]

An awesome combination of visuals and explanations

[ghatttibadi]

Hey man, Great Video. Do you mind letting us in on this software showing the lewis structure please?

[lordofmysteries]

1:10
But if we follows the rule that opposite charge attracts, then won't the partially positive Hydrogens come closer to the lone pair instead of moving away?

[smeyofficialmusic]

Hello from Cambodia, well done explaining.❤️

[DorahJames-zd]

What 3D app that you use please tell me

[butterflypooo]

OmG!! I'm reviewing my chemistry from years ago and it's sad how much I forgot ... but I kept getting stuck on why the shape of water is wedged but not something like CO2. People kept saying the EN and atom size etc ... which sort of made sense but I knew I was missing something. Then boom!! Lone pairs taking up space!!! It's so friggin simple!! Thank you!

[igwefavor]

How does the shape contribute to it's polar nature

[xxphoenixx]

I get it now! Thanks a lot, your short and nice videos help a bunch

[elecnix]

Great explanation, and supporting visuals!
One question came to mind after showing the unbounded electrons, then the positive charge of the oxygen nucleus in the same area: why doesn't the unbounded electrons cancel this positive charge? Is it because the electrons are mobile, and will migrate away? What happens to the unbounded electrons orbital?

[paraskashyap]

sir i have a quetion.(not related to this topic), in lewis dot structure of NO(nitrogen monoxide), can O donate its one electron to N (after forming double bond and N having 7 electrons in valance shell)in order to complete the valance electrons of N. I recently saw your octet rule exception video and this came in my mind. Please reply

[TheKopakah]

But if positive and negative charges atract, why don't the positive hydrogens want to migrate towards the unbonded electron pairs that cause the tetrahedral structure of the molecule?

[gowrishetty]

thankyou but if the two hydrogen atoms are on opposite sides doesnt that cancel out the effect of the negative charge and cause the molecule to be nonpolar

[Jay-oqxq]

Yes, you proved it ! Chemistry is ❤️ :)

[Mr_Roshan]

Thanks im ur subscriber
U r having a awsome explanation

[xelca]

Sir, I still have a question so when the water had a bond angle of 180° instead of 105° what is it?? Is it a polar or a nonpolar molecule?

[russell]

You still didnt answer the question as to why the water molecule is polarized due to the magnetic attraction and repulsion of the electron placement and the proton placement. When you showed the example of a nucleus with two e- bonds, the e- were 180 deg apart because the negative repulsion of the e- to the other e- is felt equally. So why does the P+ of the hydrogens bonding to the Oxygen not place the Hydrogens 180 deg away from each other if there are (2) e- pairs and (2) hydrogen bonds? 360deg divided by 2 equal forces of (+) and (-) of (2) electron pairs and (2) protons from the Hydrogens, each repelling force would be at its' maximum arc distance from its repellent charge. IE: The (2) electron bonds would be at N and S of the Oxygen and the (2) Hydrogen bonds would be at E and W of the Oxygen. Since the Oxygen has a stronger force to attract the e- to it, then the center would be more (-) and the outer would be more (+), but it the charges would still be in balance with no polarity of the water molecule. What is the reason for this unbalanced distribution of charge because these charges should be at 90 degs of each other and 180 degrees from their same charge, but they're not. The (+) charges are 104.45deg away from each other, not 180deg for a balancing of the magnetic forces.