Where are we going with this? This page will give the ability to use laboratory observations and data to compare and contrast ionic, covalent, network, metallic, polar, and non-polar substances with respect to constituent particles, strength of bonds, melting and boiling points, and conductivity; provide examples of each type.
Hydrogen Bonding
When atoms bond but…
When atoms bond but…
Hydrogen bonding is an intermolecular attraction which occurs when a hydrogen atom bonded to a strongly electronegative atom exists in the vicinity of another electronegative atom with a lone pair of electrons.
Story (sort of) time… Part 2…
So, hydrogen (H) is bopping along with one electron and it comes up to an oxygen that is missing two electrons. They decide to get together and form a covalent bond. BUT oxygen is greedy!
Oxygen's greed causes it to hog the electrons! Most of the time, all of the electrons are around the oxygen atom, leaving that part of the molecule negatively charged. As a result, the hydrogen part of the molecule is positively charged (since its electrons are being hogged by oxygen).
So, with the hydrogen side of the atom positively charged and the oxygen side negatively charged… Well, opposites attract! That's right! The electrostatic attraction between different poles of the molecule cause the atoms arrange in certain ways.
This is hydrogen bonding…
When compounds form with an unequal distribution of electrons leaving part of the molecule positively charged and another part negatively charged, though the electrons are still shared, they are not equally distributed. This results in a molecule that has positive and negative "poles" which are attracted (weakly) to each other.
So, hydrogen bonding occurs when the negatively polarized area of a molecule is attracted to the positively charged area of another nearby molecule.
Hydrogen bonds can exist either between atoms in different molecules or in parts of the same molecule. Hydrogen bonding is responsible for higher than expected boiling points of some compounds and the shape of some complex molecules (e.g. proteins).
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