Question #0c6bb
1 Answer
To put it simply: it takes more energy to separate the atoms within the molecule, and due to an unequal sharing of electrons, energy is released (meaning that there would be a greater amount of kinetic, but lower potential).
I always find it helpful to really understand the terms that thinking questions ask before I tackle it. Thus, electronegativity is defined as the ability of an atom to attract electrons from other molecules (Nelson, 2006).
If you look at the periodic table, you'll notice that as you go across groups, the electronegativity will increase. This is due to the increase in the number of charges on each element. It decreases as you go down columns since the distance from the nucleus to the valence electron shell increases.
When it becomes more electronegative, it gains electrons (negatively charged particles). The closer an element is to having a full valence shell, the less it wants to give up electrons and the more it wants to gain. It's because of it's want to gain that it requires more energy to break the bond between electron and nucleus - so the more electronegative an element is, the more it will have electrons and if paired with an element with a lower electronegativity will then cause an uneven distribution.
Potential energy is lost whenever there is a release in energy, and since there is an unequal sharing of electrons (more electrons are distributed to the element with the greater electronegativity), energy is released - meaning that as the atom attracts to another atom that has a higher electronegativity than the previous atom.
I hope that this helps a bit, and good luck!
I used my Nelson Chemistry: Human activity, Chemical reactivity textbook (2006) for some terms and Campbell Biology 10th Ed. (Google books link)
https://books.google.ca/books?id=547mBQAAQBAJ&pg=PA164&lpg=PA164&#v=onepage&q&f=false
