Okay /sci/, say I somehow had a very large vat of elemental oxygen,

>>7680082
O+O+O->O3
H+H+H+H->He4

>>7680082
Oxygen is 16 times more in mass then Hydrogen with 8 protons and 8 nuetrons to 1 proton in Hydrogen. So the ratio of mass to be the same, you need 16 parts more hydrogen than oxygen to have the same amount by mass.
If provided an ignition source, a rapid oxidization would occur leaving you with with water and some left over H2.

>>7680097
Why?

>>7680097
>O+O+O->O3
>not O+O->Si+He

Enjoy your large explosion and water.

Mostly water forms with some H2 gas

>>7680082

Depending on the temperature you could get either water or nothing

>>7680082
>elemental oxygen
>elemental hydrogen
>elemental
...perhaps you mean "molecular", but haven't the wit to know it?

>>7680105
volume doesn't depend on mass of the molecule or the atom at the 0-th order.

>>7680082
elemental oxygen doesn't exist, you will have O2 wether you want it or not.
So you can try to fill the tank with O somehow, but you will only have the equivalent of half a tank of O2.
Same goes for H.
anyway I'll assume you now have 2 half sized tanks of O2 and H2.
If temperature is high enough, O2+2H2 = H2O.

Almost all the oxygen is consumed, an equivalent quantity of water is formed, and you're left with half the H2 you started with.

>>7680182
Why would an explosion occur? Obviously because elements, but what's the actual reasoning?

>>7680082
>elemental
You've been playing too much D&D or some mmorpg