I like videogames, and I've been playing a lot of "Oxygen Not Included" recently. It's not a perfect physics simulation, but it does appear to be realistic-ish (both Specific Heat and Thermal Conductivity make up non-trivial parts of the gameplay; attempting to respect the tyranny of the rocket equation; etc.)

The latest update added in a new reaction though, that has me scratching my head a bit:

Rust (Iron Oxide) + Salt (NaCl) -> O2 + Cl

Other reactions implemented in the game make sense based on my (limited) understanding of chemistry, e.g. Iron + Carbon + Lime = Steel, or H2O+ Electrolysis = H2 and O2, so I'm wondering if there's a rational basis for the Rust -> O2 reaction as well, or if this is the devs handwaving some chemistry for gameplay purposes. (Such as, for instance, the apparent annihilation of the Sodium into heat, above)

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    $\begingroup$ No this is not a feasible reaction $\endgroup$ – Waylander Jul 5 '19 at 19:26
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    $\begingroup$ Chemistry in computer games always was and is still sloppy. Remember that you had you use fermium to research monkey brain in System Shock 2. $\endgroup$ – andselisk Jul 5 '19 at 19:31
  • $\begingroup$ @Waylander Because of heat/pressure/reactivity concerns? Can you go into more detail about the why? Is there any basis for this in reality? $\endgroup$ – Raven Dreamer Jul 5 '19 at 19:46
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    $\begingroup$ Both chlorine and oxygen are where they want to be; chlorine is most stable as Cl- and oxygen as O2-. Iron and sodium are equally in their most comfortable place. Without a lot of energy input they are not going to change. $\endgroup$ – Waylander Jul 5 '19 at 19:49

This reaction isn't feasible and won't likely occur.

Why not?

Rust and Salt are very stable, and happy with their current state. You can see this better by looking at each product.

Rust forms from Iron and Oxygen

4Fe + 3O2 → 2Fe2O3

Salt is formed from Sodium and Chlorine

Na + Cl → NaCl

The formation of both of these products is very favorable because both molecules want to bond together to complete their valence shells.

enter image description here

They do not want to break their bonds, and doing so is possible but requires a lot of energy making it unfavorable. This is why we don't see salt or rust breaking down into its elements without a high amount of energy. This all applies for the overall reaction. All the reactants are already happy and don't want to break down making this reaction, possible, but not feasible due to the high amount of energy that it takes.

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    $\begingroup$ Strike "won't likely" and replace by "will never". $\endgroup$ – Karl Jul 6 '19 at 7:50

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