Question

What two things happen when an atom's valence shell is not full?

A. The atom becomes more stable and less likely to react with other elements.
B. The atom becomes highly reactive and forms chemical bonds.
C. The atom gains additional protons.
D. The atom loses electrons.

Answer 1

An atom with an unfilled valence shell becomes highly reactive and tends to form chemical bonds, either by donating, accepting, or sharing electrons with other atoms, rather than gaining protons or spontaneously losing electrons.

Step-by-step explanation:

When an atom's valence shell is not full, two key things can happen. First, the atom becomes highly reactive, meaning that it has a tendency to interact with other atoms to attain a stable electronic arrangement. This reactivity generally leads the atom to form chemical bonds. There are two primary types of these bonds: ionic and covalent. An atom may either donate electrons to form a positively charged ion (cation), accept electrons to form a negatively charged ion (anion), or share electrons to form a covalent bond and achieve a full valence shell. Second, if an atom has an incomplete valence shell, it does not typically gain additional protons or lose its existing electrons spontaneously; rather, such changes require chemical reactions.