Why do elements want to achieve a stable state?

[LabRat1]

The universe as we know wouldn't exist if it weren't for all the elements and compounds reacting with each other, trying to achieve a stable state. But why the hassle? How does it benefit them by attaining a stable state?

 

Thanks in advance.

[Sensei]

The universe as we know wouldn't exist if it weren't for all the elements and compounds reacting with each other, trying to achieve a stable state. But why the hassle? How does it benefit them by attaining a stable state?

 

Lower energy state.

 

If atom/molecule emits photon, it reaches lower energy level.

To increase to higher energy level, it must receive energy from external source.

 

Constant temperature is when atoms/molecules receive as much photons as much as they emit to environment around it.

Atoms/molecules around object, on the surface, are emitting photons to outer space, and these photons are typically never going back, so the whole object cools down over time.

 

 

Edited January 4, 2017 by Sensei

[studiot]

What do you mean by stable?

 

If you think about it something akin to the law of natural selection must be in operation.

 

If a substance reaches an unstable state A then , by definition, it will not last very long in that state compared with a more stable state B.

 

We do also distinguish two drivers in processes chemical and other interactions.

 

Firstly a system tends to a state of minimum energy.

 

Secondly a system tends to a state of maximum entropy.

 

Changes occur that promote these tendencies, which may be in the same direction, but sometimes they are in opposition, and yet other times only one will be operating.

[Sriman Dutta]

All elements like to form chemical bonds. So, they lose electrons or gain electrons to form anions and cations respectively. They start exerting an electrostatic force of attraction and pull each other together. It's the most simple bond.

Another one is the covalent bond which involves sharing of electrons between atoms.

Then there is the coordinate covalent bond, which involves partial donation from only one atom.

[StringJunky]

Could it be related to the fact that things tend to move in the path of least resistance and once that's achieved they will stay there?

[swansont]

In a classical systems, things move toward lower energy because F = -grad U (U is the potential energy). IOW there is a force that pushes things "downhill", or toward lower energy.

 

In QM we lose the notion of having a trajectory or where this gradient makes as much sense, but there are still attractive forces and things tend to lower energy states. Non-stable states have higher energy than stable states.

 

In another view, the system loses energy (e.g. by emitting a photon) because it can. You can't lose energy if you're in the lowest energy state (or if some other conservation law prevents you from getting to that state). One of the big differences with QM is that this does not happen continually (the states are quantized) and becomes probabilistic.

[Fuzzwood]

Because there is not energy present in the rest of the system to keep them in an unstable state. Compare it by pouring hot and cold water together. Eventually the system will reach the same temperature throughout, and then cool down to reach the same temperature as the greater system (the room the container is in).

[StringJunky]

In a classical systems, things move toward lower energy because F = -grad U (U is the potential energy). IOW there is a force that pushes things "downhill", or toward lower energy.

 

In QM we lose the notion of having a trajectory or where this gradient makes as much sense, but there are still attractive forces and things tend to lower energy states. Non-stable states have higher energy than stable states.

In another view, the system loses energy (e.g. by emitting a photon) because it can. You can't lose energy if you're in the lowest energy state (or if some other conservation law prevents you from getting to that state). One of the big differences with QM is that this does not happen continually (the states are quantized) and becomes probabilistic.

Right.

Edited January 5, 2017 by StringJunky

[Itoero]

The universe as we know wouldn't exist if it weren't for all the elements and compounds reacting with each other, trying to achieve a stable state. But why the hassle? How does it benefit them by attaining a stable state?

 

Thanks in advance.

What do you mean with 'stable'? There is no strict border between stability and instability.

 

You might call it survival of the most stable states. States which are stable enough can be measured/studied.

 

Reactive oxygen species https://en.wikipedia.org/wiki/Reactive_oxygen_species

are very reactive and have short half lifes (you can call them very unstable) so measuring them is very difficult. That's why they measure a more stable footprint of ROS, like TBARS.

[swansont]

What do you mean with 'stable'? There is no strict border between stability and instability.

 

 

 

Stable = does not decay. Unstable = decays. That's a fairly strict border.

 

"Not observed to decay" is a little bit fuzzy, but that pushes lifetimes out to at least trillions of years (since we can and have identified isotopes with billion year half-lives)

[Itoero]

Stable = does not decay. Unstable = decays. That's a fairly strict border.

 

"Not observed to decay" is a little bit fuzzy, but that pushes lifetimes out to at least trillions of years (since we can and have identified isotopes with billion year half-lives)

Doesn't that 'definition' changes when you deal with other science?

Chemical stability refers to the tendency of a material to resist change.

[studiot]

I think itoero made the same point I did earlier in post#3

 

What do you mean by stable?

 

Further surely this is a chemistry question since it refers to all these compounds reacting with each other, not isotope decay.

Edited January 5, 2017 by studiot

[swansont]

 

Further surely this is a chemistry question since it refers to all these compounds reacting with each other, not isotope decay.

 

 

It says atoms, too. That brings nuclear and atomic stability into it. There are unstable states that last a long time but in physics, but we've got that covered: we call them metastable.

[studiot]

 

 

It says atoms, too. That brings nuclear and atomic stability into it. There are unstable states that last a long time but in physics, but we've got that covered: we call them metastable.

 

Neither Post#1 nor the title mention atoms on my screen.

 

And it is posted in the Chemistry section.

Edited January 5, 2017 by studiot

[swansont]

 

Neither Post#1 nor the title mention atoms on my screen.

 

And it is posted in the Chemistry section.

 

 

You're right, it says elements. Atoms were mentioned in a response.

[studiot]

 

 

You're right, it says elements. Atoms were mentioned in a response.

 

Thank you for drawing the short straw.

This proves the text entry editor is behaving normally for me in other threads.

 

 

Of course the concepts of stability also apply to particles, great and small.

So yes given the vagueness of the word 'stable' as used here the scope could easily be extended.

 

I do think, however, it is important to emphasize the difference between stability and equilibrium, which are different things.

[LabRat1]

All these answers seem to like give a reason by which an element wants to become stable like the physical or chemical phenomena behind it...but what I'm asking is different..just think, why do atoms/elements want to achieve a stable state by lowering their energy or coming into some sort of equilibrium...what does it really gain by attaining a stable state.

[Strange]

It is a natural tendency for systems to approach a minimum energy state. This is related to entropy (I think).

 

As for why this is; that's just the way the universe works. That is not a physics question. It belongs to Philosophy or Religion.

[LabRat1]

It is a natural tendency for systems to approach a minimum energy state. This is related to entropy (I think).

 

As for why this is; that's just the way the universe works. That is not a physics question. It belongs to Philosophy or Religion.

Right Right