The structural formula of a molecule shows the arrangement of atoms in the molecule and the bonds between them. In the case of water (H2O), the correct structural formula is H-O-H, not H-H-S. This is because oxygen (O) forms two bonds, not one like sulfur (S) does. Therefore, in water, each hydrogen atom is bonded to the oxygen atom, not to each other. So the correct representation should show the H atoms bonded to the O atom, not to each other.
