For each of the following bonds, indicate the positive end with 𝛿⁺ and the negative end with 𝛿⁻ . Draw an arrow to show the dipole for each.
a. N and F

Verified step by step guidance

1. Step 1: Understand the concept of electronegativity. Electronegativity is the ability of an atom to attract shared electrons in a chemical bond. The greater the difference in electronegativity between two atoms, the more polar the bond will be.
2. Step 2: Look up the electronegativity values of nitrogen (N) and fluorine (F). Fluorine has an electronegativity of approximately 3.98, while nitrogen has an electronegativity of approximately 3.04.
3. Step 3: Determine the direction of the dipole. Since fluorine has a higher electronegativity than nitrogen, it will attract the shared electrons more strongly, making fluorine the negative end (𝛿⁻) and nitrogen the positive end (𝛿⁺).
4. Step 4: Represent the dipole with an arrow. Draw an arrow pointing from the less electronegative atom (N) to the more electronegative atom (F). Place a small plus sign (+) at the tail of the arrow near nitrogen to indicate the positive end.
5. Step 5: Label the bond. Clearly mark the nitrogen atom with 𝛿⁺ and the fluorine atom with 𝛿⁻ to indicate the partial charges due to the unequal sharing of electrons.

Key Concepts

Electronegativity

Electronegativity is a measure of an atom's ability to attract and hold onto electrons in a chemical bond. In the context of the bond between nitrogen (N) and fluorine (F), fluorine is more electronegative than nitrogen, meaning it pulls the shared electrons closer to itself, creating a dipole moment.

Dipole Moment

A dipole moment occurs in a polar bond where there is an uneven distribution of electron density. It is represented by an arrow pointing from the positive end (𝛿⁺) to the negative end (𝛿⁻) of the bond. In the N-F bond, the dipole moment indicates that the electrons are more concentrated around fluorine, making it the negative end.

Polar vs. Nonpolar Bonds

Bonds can be classified as polar or nonpolar based on the difference in electronegativity between the two atoms involved. A polar bond, like that between N and F, has a significant difference in electronegativity, resulting in a dipole moment. In contrast, nonpolar bonds occur between atoms with similar electronegativities, leading to an even distribution of electron density.