A water molecule contains two hydrogen atoms bonded with an oxygen atom. That is, formula of water is .
Since there is high difference in electronegativity of both hydrogen and oxygen. Thus, there will be uneven distribution of charge on a water molecule as hydrogen will have a positive charge whereas oxygen will have a negative charge.
This will also make the water molecule polar in nature.
One thing that does not change is the chemical composition of water, which is still H2O. And maybe mass, if all of the particles remain inside the beaker, which was never mentioned in the question so I am not sure.
