Covalent bonding occurs between atoms when 1. The potential energy of the shared elec- trons is lower in the bond than it would be if the electrons were not shared between two nuclei 2. The potential energy of the shared elec- trons is independent of the covalent bond, but the potential energy of the newly formed molecule is greater than the individual atoms 3. Covalent bonding occurs when the octet rule is satisfied regardless of the potential en- ergy of the shared electrons 4. The potential energy of the shared elec- trons is higher in the bond than it would be if the electrons were not shared between two nuclei

The potential energy of the shared elec- trons is lower in the bond than it would be if the electrons were not shared between two nuclei

Explanation:

The entire essence of chemical combination is the attainment of a lower potential energy.

When two atoms are isolated at a large distance from each other, the potential energy is high.

However as the nuclei of the two atoms approach each other, the potential energy decreases until a minimum is attained. The distance between the nuclei at this point is the bond distance.

Hence, the potential energy of the shared electrons is lower in the bond than it would be if the electrons were not shared between two nuclei.

atomic mass = 39

number of neutrons = 20

number of protons= 19

electronic configuration = 1s2 2s2 2p6 3s2 3p6 4s1

the number of electron in first shell = 2

number of electrons in n=3 shell = 8