Chemical Bonding

Electrostatic attraction. While electrons do move around, the number of protons I the nucleus remain the same. The electron transfer creates positive and negative ions that hold each other together.

>>9095856
>why would two neutral atoms such as Na and Cl not just stay as neutrally charged atoms?
Because the movement of electrons is energetically favorable.

>>9095856
Each atom is more stable as ion rather than the neutral state. The reason for this is because each atom is the most stable when it has enough electrons to "fill" all orbitals fully.

>>9095856
So you have two balls of positive charge. One has three positive charges on it and the other one. They both have one electron, but because of the 3 to 1 disparity in positive charge the electron from the +1 ball is transferred to the +3 ball. This is why electron transfers occur and the phenomena is a bit more complex than that and is described under electronegativity (EN). Basically the more relatively EN an atom or molecule is the more likely it is going to scavenge nearby electrons over other atoms/molecules in the system.

Na and Cl are not stable naturally they are both, when not bound, lacking an electron and with too many electrons respectively. If they find a partner that is more willing to give up it's electron, for Na, or more willing to accept an electron, Cl, than the original salt pairing it will break the ionic bond. In the most common case of water this is almost a done deal as the water forms a hydration sphere around the charge making a large field of opposing charge dissolving the NaCl into Na+ and Cl-.

>>9095856
Good question, I'll attempt to answer it for the ionic case and then generalize it a bit.

A chemical bond is essentially the spreading out of electrons to attain the lowest possible potential energy. For example, a neutral Sodium atom has only one valence electron. Electrons don't like to be alone at all, and as a result, the atom has a high electronic potential energy (side note- asking WHY the electron desperately wants to be paired with another is another subject entirely. It is a law of nature and we need to accept it in order to develop any picture of bonding). But, if the Sodium ion is positively charged, it has the magic number of eight electrons, and therefore has a lower "potential" to react with other species. If we assume that a Chlorine atom stole the electron from the Sodium, we now have two opposite charged atoms with full valence shells. These atoms have a very low reaction potential, but will be drawn near to each other due to the electrostatic attraction. This is called an ionic bond.

A more common kind of bond is a covalent bond, in which the valence atomic orbitals of two or more atoms are combined into multiple "molecular orbitals". The cause of this is constructive interference between the valence electrons (remember that electrons have wave properties). The molecular orbitals that contribute to the covalent bond will always be lower in energy than the atomic orbitals that contributed the electrons, so still, all that's really happened is that electrons are combining in a way that minimizes their potential energy.

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>>9096198
>>9096128
>>9096101
Thanks guys. I think I get it now.

>>9096198
>A chemical bond is essentially the spreading out of electrons to attain the lowest possible potential energy.

Good post anon. Question: is entropy just describing the process by which all matter is gradually approaching a lower and lower potential state over time?

>>9096328
Good question, now we're talking some serious shit.

The way I see it, the universe and everything in it is essentially doing two things: cooling down and spreading out. When a chemical bond is formed, the "system" (atoms/molecules involved in the reaction) loses potential energy, but this energy has to go somewhere- it's lost as heat, increasing entropy of the surroundings (universe). Of course, some reactions are endothermic, and therefore require energy to make bonds, but this means that the entropy of the system is going to increase (side note: a good working definition of entropy is "the extent to which something is spread out").

So, in a sense, entropy is an emergent phenomena that stems from a more fundamental process: the minimization of potential energy in any electronically interacting system.

OR, you could view it the other way around. One could say that this strange rule of minimal potential energy is a direct result of a perpetual increase in entropy- a constant spreading out of heat, matter, and energy- that governs every electronic interaction in existence.

>>9095856
Why are Chlorine atoms green and Sodium atoms silver?