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:

• For \(O_3\): The bonds in \(O_3\) are between oxygen atoms. Since the atoms are of the same element, the electronegativity difference is zero. So, the bonds are non - polar.
• For \(S_8\): The bonds in \(S_8\) are between sulfur atoms. As the atoms are identical, the electronegativity difference is zero. Thus, the bonds are non - polar.
• For \(O_2^{2 - }\): The bonds in \(O_2^{2 - }\) are between oxygen atoms. With no electronegativity difference (same element), the bonds are non - polar.
• For \(BH_4^{-}\): Boron (\(B\)) has an electronegativity of approximately \(2.04\) and hydrogen (\(H\)) has an electronegativity of approximately \(2.20\). There is a small electronegativity difference (\(\Delta\chi=2.20 - 2.04=0.16\)). Although small, this difference means the \(B - H\) bonds are polar.
• For \(NO_3^{-}\): Nitrogen (\(N\)) has an electronegativity of approximately \(3.04\) and oxygen (\(O\)) has an electronegativity of approximately \(3.44\). The electronegativity difference (\(\Delta\chi = 3.44-3.04 = 0.4\)). This difference indicates that the \(N - O\) bonds are polar.

Answer:

\(BH_4^{-}\), \(NO_3^{-}\)