Final answer:
Sodium is more likely to be a cation than chlorine because it more readily loses its single valence electron, resulting in a sodium cation (Na+), while chlorine gains an electron to form a chloride anion (Cl-) due to its higher electronegativity.
Step-by-step explanation:
The reason why sodium is more likely to be a cation than chlorine is due to its tendency to lose electrons more readily. The option C) Sodium tends to lose electrons more readily than chlorine is the correct answer. Sodium has only one valence electron, and it takes less energy for sodium to donate that one electron than to accept seven more to fill the outer shell. If sodium loses this electron, it attains a stable electron configuration with a net positive charge, thus becoming a sodium cation (Na+).
On the other hand, chlorine has seven electrons in its outer shell and a relatively high electronegativity, which means it is more efficient energetically for chlorine to gain one electron than to lose seven, forming a chloride anion (Cl-) with a net negative charge. This process of electron transfer between sodium and chlorine leads both to achieve the octet rule, resulting in stable electron configurations for both ions.
The ionic bond formed between the positively charged sodium cation and the negatively charged chloride anion is due to the strong electrostatic attraction between the two oppositely charged ions. This attraction is the basis of the formation of sodium chloride, or common table salt.