Question

use what you learned from the readings to answer the question on the right. which of the following molecules or ions contain polar bonds? o₃ s₈ o₂²⁻ bh₄⁻ no₃⁻

Explanation:

A polar bond occurs when there is a significant difference in electronegativity between the atoms forming the bond.

• \(O_3\): The bonds are between oxygen atoms (same element), so no significant electronegativity difference. Non - polar bonds.
• \(S_8\): Bonds are between sulfur atoms (same element), so no significant electronegativity difference. Non - polar bonds.
• \(O_2^{2 - }\): Bonds are between oxygen atoms (same element), so no significant electronegativity difference. Non - polar bonds.
• \(BH_4^-\): Boron (\(B\)) and hydrogen (\(H\)) have a small electronegativity difference (\(\Delta EN= 2.2 - 2.04=0.16\)). But the symmetrical tetrahedral geometry makes the overall molecule non - polar in terms of dipole moment (since the bond dipoles cancel out).
• \(NO_3^-\): Nitrogen (\(N\)) and oxygen (\(O\)) have a significant electronegativity difference (\(\Delta EN = 3.44 - 3.04 = 0.4\)). So, it contains polar bonds.

Answer:

\(NO_3^-\)