Draw the Lewis Structure for H2O: Determine the Number of Electron Groups, the Electron Geometry, and the Molecular Shape. Is it Polar or Nonpolar?

The Lewis structure of water (H₂O) can be drawn by following a few simple steps:

1. Count the total number of valence electrons: Oxygen has 6 valence electrons, and each hydrogen has 1, giving us a total of 8 valence electrons (6 + 2).
2. Next, place the oxygen atom in the center and connect it to the two hydrogen atoms with single bonds. This uses 4 out of the 8 valence electrons.
3. This leaves us with 4 electrons. Place these 4 electrons as two lone pairs on the oxygen atom.

The resulting Lewis structure looks like this:

   H
   |
O -- H
   .. 

Now, let’s determine the number of electron groups around the central oxygen atom. There are two bonds to hydrogen atoms and two lone pairs, making a total of 4 electron groups.

The geometry around the oxygen atom can be determined using the VSEPR (Valence Shell Electron Pair Repulsion) theory. With 4 electron groups, the electron geometry is tetrahedral.

However, when considering only the atoms, the molecular shape of H₂O is bent or angular due to the two lone pairs pushing the hydrogen atoms closer together.

As for polarity, water is a polar molecule. The electronegativity difference between oxygen and hydrogen causes a slight negative charge on the oxygen and a slight positive charge on the hydrogens, resulting in a dipole moment. This polarity is crucial for many of water’s unique properties, such as its solvent capabilities and high surface tension.