Question

What does it mean for an atom to be electronegative? How does this affect the shape and overall charge of a water molecule?

Answer 1

Explanation:

Electronegativity describes the tendency of an atom (or functional group) to attract electrons toward itself. This chemical property is affected by the atomic number and the distance that the atom's valence electrons reside from the charged nuclei. If we take a look at the periodical table we can see that electronegativities increase from left to right across it, this means that elements on the left will have low electronegativities, therefore, they are electropositive elements (F > O > N > C). We can also observe that electronegativities decrease from top to bottom (F > Cl > Br > I).

Hydrogen has an electronegativity of 2.0 and oxygen has 3.5, the electrons are drawn significantly towards the more electronegative element, oxygen, but the atoms do not become ionized but partially negative charged, whereas the hydrogen atoms have partial positive charges (You can see this in the image I annexed). This means that water is a polar molecule because both hydrogen atoms are attracted to the same side of the oxygen atom, their positive charges make them far apart from each other.

I hope you find this information useful and interesting! Good luck!