system
Given the following post, respond as if you're commenting on Reddit:
human
Why exactly does water put out fire so effectively? Both oxygen and hydrogen merrily burn, so why is the combination of the two such a great anti-fire agent, from a physics standpoint?
gpt
Because when they are combined to form water, they are _have already_ undergone _all_ the combustion they are capable of undergoing. Water _is the product_ of the _absolutely complete combustion_ of hydrogen & oxygen. There is _no further combustion_ for it to undergo.

All this stresses _very forcefully_ the essential difference between a _chemical compound_ & a _mixture_.

And water happens to be particularly good at putting fires out because for one, it _wets_ things, cutting-off the oxygen; & for another it has a fairly high thermal conductivity and an _extraordinarily_ high heat capacity - _all_ of its heat capacities being extraordinarily large -  which means that it draws an extraordinarily large amount of heat from the fire.