When heated at extreme temperatures, water can spontaneously decompose.
According to Wikipedia (https://en.wikipedia.org/wiki/Water_splitting):
In thermolysis, water molecules split into their atomic components hydrogen and oxygen. For example, at 2200 °C about three percent of all H2O are dissociated into various combinations of hydrogen and oxygen atoms, mostly H, H2, O, O2, and OH. Other reaction products like H2O2 or HO2 remain minor. At the very high temperature of 3000 °C more than half of the water molecules are decomposed, but at ambient temperatures only one molecule in 100 trillion dissociates by the effect of heat. The high temperatures and material constraints have limited the applications of this approach.
At those temperatures, will the hydrogen and oxygen (and combination of those) still react to form water? If so, could this be considered a dynamic equilibrium?