The hydrosphere is composed of water, which is made up of hydrogen and oxygen, in the formula H20. P.E
The chemical component of hydrosphere (water) is Oxygen and Hydrogen.
2H + O = H2O (water). The other chemical compound is Salt water which a mixture of Sodium and Water. NaCl(aq) (salt water). R.D
350px-Water_molecule.png

There are other chemical compounds present in sea water such as NaCl, Carbon, Sulfur etc.
Seawater composition.png
This is from Wikipedia. B.H