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7:36 PM

Guys, I just realized (from the chemistry book I'm reading) about the laws of conservation of matter. Nothing really disappears, that's mind-blowing! Even if you kill someone, his atoms will still live. That's really cool.

(lol there is no one online, who am I chatting to xD)

ACuriousMind

@NovaliumCompany Except...there is no law of conservation of matter :P

Novalium Company

:-| wut

Conservation of mass

The law of conservation of mass or principle of mass conservation states that for any system closed to all transfers of matter and energy, the mass of the system must remain constant over time, as system's mass cannot change, so quantity cannot be added nor removed. Hence, the quantity of mass is conserved over time. The law implies that mass can neither be created nor destroyed, although it may be rearranged in space, or the entities associated with it may be changed in form. For example, in chemical reactions, the mass of the chemical components before the reaction is equal to the mass of the...

ACuriousMind

I mean, it's true that chemical reactions will not alter the nuclei of atoms, but that doesn't mean atoms are immutable

Novalium Company

Yes, of course. I'm just saying that atoms live forever.

and never get destroyed nor created?

ACuriousMind

@NovaliumCompany The second half of the intro of that article already tells you that it's only an approximation that holds well in chemistry or classical mechanics

@NovaliumCompany That's entirely false

Novalium Company

7:42 PM

Well, when we have a chemical reaction the reactants must always equal the product, meaning, atoms can't be destroyed nor created?

ACuriousMind

@NovaliumCompany Sure, but chemical reactions are not the only way atoms can interact. Nuclear fusion and nuclear fission are examples of reactions that do create/destroy atoms.

Chemistry is not concerned with such reactions, but that doesn't make "conservation of atoms" a law of nature

It's just a law that holds in the subset of nature chemistry is concerned with

Novalium Company

Well, nuclear fussion/fission just join or split atoms, that's it, they don't create or destroy?

Anonymous

Well, that creates new atoms from existing ones

ACuriousMind

@NovaliumCompany They certainly create new atoms. If you mean that they don't change the number of protons or neutrons, that's true, but consider that e.g. $\beta^+$-decay turns a proton into a neutron.

danielunderwood

@NovaliumCompany this may be the most well-known example en.wikipedia.org/wiki/Pair_production

Anonymous

7:46 PM

What do you mean by "destruction" of atoms though?

Anonymous

Just vanishing randomly? :P

danielunderwood

(Though that isn't with atoms)

Novalium Company

@Blue Exactly :D

I mean, like atoms appearing from nowhere, that's what I mean by creating atoms.

ACuriousMind

Well, no, atoms don't appear from "nowhere". But that doesn't mean mass - or matter - is conserved.

Conservation is a much stricter concept than "stuff doesn't just appear randomly".

Novalium Company

What I meant from the beginning is that if you have a single atom, it cannot disappear, it can just combine, split, but not disappear?

ACuriousMind

7:51 PM

Well, it could meet an anti-atom and annihilate into a bunch of photons.

But sure, it can't just vanish from existence without a trace.

Novalium Company

meaning disappear, since photons don't have mass?

Sorry, it's really late and my mind started wondering around the atomic world and conservations... :D

Anonymous

You might be interested in reading this:

Anonymous

Antimatter

In modern physics, antimatter is defined as a material composed of the antiparticle (or "partners") to the corresponding particles of ordinary matter. In theory, a particle and its anti-particle (e.g., proton and antiproton) have the same mass as one another, but opposite electric charge and other differences in quantum numbers. For example, a proton has positive charge while an antiproton has negative charge. A collision between any particle and its anti-particle partner is known to lead to their mutual annihilation, giving rise to various proportions of intense photons (gamma rays), neutrinos...

Anonymous

@NovaliumCompany Well, depends on what you define as "disappear"

Anonymous

The atom will obviously no longer exist

Novalium Company

7:57 PM

Ok, I'll be wondering around the topic tommorow. I'll go to sleep cuz tommorow I'm going to Greece on a trip for a week, so I'll be gone for a week, but I'll think about the topic. Thanks and see you :-)

Anonymous

Wow, Greece! Have a nice trip :D

Anonymous

Goodnight

Novalium Company

@Blue Thanks. :P