Covalent bond is the term that is being used to describe the bonds in the compounds that are created due to the sharing of one or more electrons. One of the best example of the simplest covalent bond is the bond that is being created when two isolated hydrogen atoms come together to form an H2 molecule. An isolated hydrogen atom has one proton and electron being combined by the force of attraction from the opposite-charged articles. When a pair of isolated hydrogen atom combines, two forces of attraction are created coming from each of the isolated hydrogen atom.
Answer:
The structures are attached in file.
Hydrogen bonding and intermolecular forces is the reason for ranks allotted.
Explanation:
In determining Lewis structure, we calculate the overall number of valence electrons available for bonding. Making carbon (the least electronegative atom) the central atom in the structure, we allocate valence electrons until each atom has achieved stability.
In order of decreasing affinity to water molecules:
This is due to the fact that the 
will accept protons more readily than the bicarbonate ion, 
. Carbonic acid, 
will not accept any more protons, hence it is the least attractive to water molecule, even though soluble.
Answer:
c and d are correct
Explanation:
In A, false because in Valence Electrons, the more the valences, the more stable an atom is.
In B, false because atoms cannot readily gain or lose valence electrons as the number of valence electrons is determined by the column they are in.
In C, true because the more the valence electrons, the more the stability of an atom.
In D, true as electron placing is important and the reactivity of an atom is important.
So C and D are true!
