polar and non polar molecules

[Esmeralda Gonzalez 3G]

Just wanted to clarify how we figure out which part of a structure would have the negative polarity and which part would have positive polarity. For example, in water, oxygen is the more negative pole and the two hydrogens are more positive, but what factors determine this?

[305920501]

Due to the electronegativity difference between hydrogen and oxygen, the electrons are unevenly shared among the atoms in the molecule. This makes the bonds polar and therefore creates an unsymmetrical shape that causes the entire molecule to be polar based on the distribution of charge.

[Steven Tjandra 1B]

Hello,

If we think back to what exactly it means to be negative, its just that something has an extra electron. So, in a covalent bond, even though it's a sharing of electrons, one atom can kinda morph the bond a bit more towards itself, making it partially negative. That tends to happen when a really electronegative atom who really wants an electron is bonded to a not so electronegative atom, which is fairly chill. So in water, Oxygen is more electronegative than Hydrogen, so it becomes partially negative. When determining polarity, it's also important to consider the shape of the molecule. If water was a linear shape, the two OH bonds would cancel each other out and the molecule would likely be non polar. However, since water is bent, there isn't an equivalent OH bonds on the other side to balance out the polarity, leading water to be polar.

Slightly positive,
Steven Tjandra