Final answer:
The difference in electronegativity between bonded atoms determines the type of bond formed - ionic or covalent. A larger difference favors an ionic bond, while a smaller difference favors a covalent bond. There are exceptions to this trend.
Step-by-step explanation:
The difference in electronegativity between bonded atoms is an important factor in determining the type of bond formed - ionic or covalent. The greater the difference in electronegativity values, the more likely the bond will be ionic. On the other hand, if the electronegativity difference is small or zero, the bond will be covalent and nonpolar.
For example, the electronegativity difference between hydrogen (H) and chlorine (Cl) in H-Cl is 0.9, which indicates a polar covalent bond. However, the electronegativity difference between sodium (Na) and chlorine (Cl) in NaCl is 2.1, suggesting an ionic bond.
Overall, the correlation between the difference in electronegativity and the tendency to form ionic or covalent bonds is that a larger difference favors the formation of an ionic bond, while a smaller difference favors a covalent bond. It is important to note that there are exceptions to this general trend.