Given the following electronegativities: Na = 0.9, H = 2.1, Cl = 3.0 which of the following statements is true?

Question

Quizplus · Accepted Answer

To determine whether a bond is polar or nonpolar, you need to compare the electronegativities of the two atoms involved in the bond. If the difference in electronegativity is between 0 and 0.4, the bond is nonpolar covalent. If the difference is between 0.5 and 1.9, the bond is polar covalent. If the difference is greater than 2.0, the bond is ionic. In this case, Na and H have a difference in electronegativity of 1.2 (2.1 - 0.9), which falls in the range for polar covalent bonds. Therefore, H₂ is a polar covalent molecule. Cl and H have a difference in electronegativity of 0.9 (3.0 - 2.1), which is in the range for polar covalent bonds. Thus, HCl is a polar covalent molecule. Finally, the electronegativity difference between Cl and Na is 2.1 (3.0 - 0.9), which is greater than 2.0. Therefore, NaCl is an ionic compound. Alternatively, you could also reason that Na is a metal and Cl is a nonmetal, so NaCl is an ionic compound. In contrast, both H and Cl are nonmetals, so their bond will either be polar covalent or nonpolar covalent. Since H and Cl have a significant difference in electronegativity, HCl is a polar covalent molecule. Cl₂, on the other hand, consists of two identical nonmetal atoms, so it is a nonpolar covalent molecule.

Given the Following Electronegativities: Na = 0