Question

select the correct answer. which statement best explains how electrons form a covalent bond in a molecule? a. a pair of electrons splits so that each atom gets one electron. b. a pair of electrons belongs to two atoms at the same time. c. a pair of electrons is transferred from one atom to another atom. d. a pair of electrons moves from a lower energy level to a higher energy level. e. a pair of electrons drifts freely from one molecule to another.

Explanation:

To determine the correct answer, we analyze each option based on the concept of covalent bonding:

• Option A: Electrons in a covalent bond do not split; they are shared, so this is incorrect.
• Option B: In a covalent bond, a pair of electrons is shared between two atoms, meaning they belong to both atoms simultaneously. This matches the definition of a covalent bond.
• Option C: Transfer of electrons is characteristic of ionic bonding, not covalent bonding, so this is incorrect.
• Option D: Electron movement between energy levels is related to excitation/relaxation, not covalent bond formation, so this is incorrect.
• Option E: Delocalized electrons (like in metals) drift, but covalent bonds involve shared electrons between specific atoms, not drifting between molecules, so this is incorrect.

Answer:

B. A pair of electrons belongs to two atoms at the same time.