Final answer:
An ionic bond is formed in NaCl when sodium (Na) donates an electron to chlorine (Cl), creating sodium cations (Na+) and chloride anions (Cl-), which are held together by their opposite charges.
Step-by-step explanation:
The bond formed between Na+ and Cl- in NaCl is known as an ionic bond. This occurs when a sodium atom donates an electron to a chlorine atom, resulting in the formation of a sodium cation (Na+) and a chloride anion (Cl-). These ions have opposite charges and are attracted to each other, which leads to the formation of sodium chloride or NaCl.
The energy required to remove an electron from sodium is only 5.14 eV, which allows the sodium atom to easily donate this valence electron. Chlorine, with a large electron affinity, readily accepts this electron. The result is a stable ionic compound, where the ions are arranged in a regular three-dimensional lattice structure.