If all atoms wants to be stable and forming molecules is their way of doing so, why isn’t the universe just a big batch of playdoh?


Not sure if this is chemistry or physics so I’m flairing it as ‘Other’.

In: Physics


all atoms aren’t stable. that’s exactly what happens when something radioactively decays, the atom splits and forms a new element. forming new molecules often releases or absorbs energy as well.


At the beginning of the universe, everything in existence was scattered about with tremendous energy (the big bang). Even though it would be energetically ‘easier’ for all the particles to just stop moving and coalesce into a ball of playdoh, they don’t have any easy way of slowing down.

It’s kind of like going downhill in a car when your breaks fail. Your only way of slowing down is by hitting something, whether that be a tree or another car.

Anyway, atoms will hit each other, and form bonds, releasing energy as they reach a more stable configuration (just as there may be an explosion of your gas tank when you collide with another car).

One could say that we’re currently careening out of control downhill, just killing time until our car finally slams to a halt. That point is referred to as “heat death” by physicists, and essentially means that all energy has been equally distributed to form that ideal playdoh-like state.

Unfortunately, while heat death may be ideal for particles, it is less so ideal for people and civilization. At that point when all energy is equally distributed, there is no longer any ability to do work, store information, or even exist as anything but a homogeneous blob.

Going back to the car analogy, we’re no longer going anywhere once we’ve hit a wall. We might be in a ‘more stable’ position, but we’re not traveling anywhere. In fact, we’re dead.

For us human beings, we can only live our chaotic, scattered lives as the universe careens out of control. As soon as things come to a stop, we’re gone.

It was play doh in the beginning, but like play doh if you leave it long enough, it’ll change into something different, because change is the nature of the universe.

Not all atoms are more stable in bonds with other atoms. Noble gases, for example, are quite stable by themselves and don’t readily bond to anything (hence “noble”), and helium bonds with almost nothing – IIRC it will only bond with fluorine and only under extreme circumstances.

Some atoms, like fluorine, will readily bond with any damn thing. However, once it’s in a molecule, it’s already grabbing onto that thing really damn hard so it’s reluctant to grab onto something else. It absolutely will, though, if the something else forms a more stable bond.

As a more tangible example, consider oxygen. It’ll bond to itself as O2, and that’s stable *enough*. But a bond with hydrogen or carbon would be more stable. Cellulose is a major component of wood, and is made of a lot hydrogen and carbon stuck together. The hydrogen and carbon atoms need a bit of energy to make them let go of each other first, but once they do the O2 will easily break apart and grab hold of the hydrogen and carbon to make CO2 and H2O.

You’ll notice, though, that if you put a match to H2O (water) it doesn’t fall apart. That’s a very stable bond. It’s hard to get them apart. Add more oxygen and you just get O2 dissolved in H2O. Sodium, though, is even grabbier than oxygen (under certain circumstances) so when you add sodium to water, the sodium grabs the absolute shit out of OH ions and leaves that second H to wander off and join with another H, giving you NaOH and H2.

So, even if all of the matter in the universe was already in its most stable, least energetic molecular bond with other atoms, that doesn’t mean they’d all be stuck to each other.

it will be, this is called the “thermal death” of the universe. One homogeneous goo everywhere.
Like when you put milk into your coffee (if you would drink coffee at your age of 5).

But (luckily for us) it takes time. Right now the age of the universe allows for some structures to form. (like the milk in the coffee slowly spreading out, where you clearly see patches of milk and patches of coffee).