can a life form that we have no understanding of take elements for itself and create water, H2O.

Still there is no water present, well not in the form that we understand

Another entry would read that science did not discover that there can be no life without water.

My point is simple, all things can be possible, without proof, just sound speculation.

Take your table for example. If I suspend it from the ceiling, does it still have four legs.

Water may only exist on some far reaching planet under the relationship of H3OH3O2 as the hydrogen molecule cannot exist in pairs.

Natural kinds are interesting in the following sense. The finding of necessary relationships in the natural world. Natural kinds are suppose to have intrinsic properties such that the non obtaining of such properties result in the non obtaining of the kind. i.e: Water is H2o is a posteriori necessary. Here is why: For a possible world without H2O, we can confidently say there are no water. In any possible world with water, we can confidently say there are H2o.

A suspended table is a table but it has no legs like you had suggested when removing a leg from a four legged table, why wouldn't you call a three legged table a table, though it may be less stable.

Now you say water is the combination of H2O. It is a necessary relation, all I suggest is that in some place where the hydrogen molecule cannot pair but simply form into three parts, would not H3OH3O2 be water as well, which would expand your necessary relations theorum to include other possibilities.

Yes, I would say science attempts to applying relationships to the natural world, but I would look upon these relationships as dynamic and constantly changing. For example, heavy water is defined as such:

Heavy water - Wikipedia, the free encyclopedia