Polarity in water molecule and electronegativity of oxygen in that molecule.

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Water (H2O) is polar due to the electronegativity difference between oxygen and hydrogen. Oxygen, with an atomic number of 8, has a greater number of protons compared to hydrogen, leading to a stronger attraction for shared electrons in the covalent bonds. This results in the electrons being drawn closer to the oxygen atom, creating a partial negative charge on oxygen and a partial positive charge on hydrogen. The bond length of each O-H bond is approximately 95.84 picometers, and the bond angle is 104.45 degrees, which positions the hydrogen atoms further apart from each other than from the oxygen atom. The discussion highlights that the size of an atom is influenced by its electron cloud, with more protons resulting in a stronger pull on electrons, thus affecting the overall polarity and molecular structure of water.
AakashPandita
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H20 is polar in nature.
It is fundamentally because oxygen is more electronegative than hydrogen and the shared electrons tend to be near oxygen.
This may be because the atomic number of oxygen is more than that of hydrogen.
But in the bond I don't understand how the 2 shared electrons experience more force from the oxygen side than they do from the hydrogen side.
As the 2 electrons are experiencing the force of 2 protons from both the sides.
Are you getting it, what I am trying to convey?
 
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AakashPandita said:
As the 2 electrons are experiencing the force of 2 protons from both the sides.

Oxygen has more than 1 proton. Because of this, the nucleus of oxygen has a greater affinity for electrons than hydrogen.
 
It is to do with ionization energies. When you go from left to right (and up) you encounter smaller atoms. Which means that the proximity of their electrons is a lot closer than a larger atom. Due to the fact that the Oxygen electrons are a lot closer to the nucleus of the atom a higher amount of energy is required to pull them apart. :) Hope this helped
 
Also, as Matt states, the oxygen is closer to each hydrogen atom than each hydrogen atom is to each other. Each OH bond in H2O is ≈95.84 pm. The bond angle is 104.45°, making the hydrogen atoms 177.38 pm apart.
 
MattA147 said:
Due to the fact that the Oxygen electrons are a lot closer to the nucleus of the atom
Why? This I am not able to understand.
 
Well, most of an atom's size is taken up by it's electron cloud. Having more protons means wanting more electrons. Oxygen's atomic number is 8, so it has 8 protons and 8 electrons in ground state. Hydrogen only has 1 proton, so it only has 1 electron. And more electrons means a larger atom.
 
why closer?
 
In short, so it doesn't get too confusing:

500px-Electron_shell_001_Hydrogen.svg.png
500px-Electron_shell_008_Oxygen.svg.png
 
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