Each hydrogen bond will form ONE COVALENT bond with the other atoms in the molecule. Hydrogen has only one atom; to form a covalent bond, it has to donate one electron and the other atom that hydrogen is bonding with will donate one electron also, making two. These two electrons will be shared between the two, making the atoms to have two electrons each.
The surface area of a sphere can be approximated as follows: Surface area = 4πr2; where r is the radius of the sphere; π is a constant that is roughly equal to 3.
