Average age the water molecules we live with: billions of year

>>8481327
define age

>>8481327
The atoms that make up our water are as old as the earth, but if you consider a water molecule that disessembles then reassembles to be new on each ressembly then no water is pretty new

>>8481328

water molecule age: timeinterval from "three individual atoms (2xH, 1xO) combining to a single water molecule" until "one of the atoms leaves the molecular structure" (maybe being replaced by another individual atom, maybe rejoining the structure)

>>8481332

does this really mean, that even a single water molecure dissembles/reassembles continously? Which is a typical time frame for a dissembling/assembling cycle (room temperature, ~20°C)?

Wow, sounds fascinating... sounds like it's worth further reading... if the process of split/merge is endothermic, then water would faster lose energy and freeze, I guess...

>>8481339
>single molecule blah, blah?
no?
In solution (water in liquid water), there is formal dissociation of water into H+ and OH-, and these ions are well solvated.
The direct association of the very same individual ions formed initially is unlikely, rather they react with solvent molecules in the solvation shell.
Overall there is dynamic equilibrium described by Kw at a given T.

TL;Dr water molecules are swapping H-atoms on an ongoing basis.

>>8481327
>In school they said most water is "as old as the earth"
This statement probably invokes the idea that water was brought to earth via comets and/or asteroids.

Molecules don't have an individual identity. You can't follow water molecules and say that the water molecules A and B you saw previously are the same as the molecules C and D you see now, rather than being D and C.

>>8481725
Disregard that, it's true but shouldn't stop you from finding an average age.