Write and by the appropriate atoms and draw a dipole moment vector for any of the following molecules that are polar: (a) HF (b) IBr (c) Br2 (d) F2

The dipole moment refers to the separation of charges in the molecule. Atoms are in opposite directions. (a) HF. F is more electronegative. The vector is pointing F. (b) IBr. The vector points Br.

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The dipole moment can be used to analyze the molecule's polarity.

Let us say that a molecule is composed of an element with a positive charge  (E1 ⁺) and another element with a negative charge (E2⁻). These two elements are separated by a distance d.

               E1 ⁺  --------- (d) ----------- E2⁻        

              (+Q)                                 (-Q)

Each element has a charge magnitude, Q. Depending on the charge, Q can be either positive (+Q) or negative (-Q).

When +Q = -Q, the dipole moment is represented with a μ letter, and it equals the product between the magnitude of the charge, Q, and the distance, d.

                                              μ = Q x d

Now, let us analyze the molecule estructure.

The covalent bond that joins two atoms is composed of two electrons.

If one of the atoms is more electronegative, it pulls the electrons to its side.      

This is represented with an arrow carrying a positive symbol,  +→ . The arrow is directed to the position of the electronegative atom.

The highest density of electrons surrounding one of the atoms is represented as δ⁻, while the lowest density of electrons is represented as δ⁺.        

In these situations, in which charges are different, and there is a separation of charge in the molecule, we can say that molecules are polarized.  

These molecules have a dipole moment, and when representing them, the direction of the dipole moment arrow is always pointing to the most negative atom.

In the attached files you will find the molecules    

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You can learn more about dipole moment at

link

See explanation and image attached

Explanation:

A molecule is said to have a dipole moment whenever there is a separation of charge in the molecule. When this occurs, one end of the molecule is positive while the other end is negative. The molecule is now said to be polar.

If two atoms in a molecule have a significant difference in electronegativity between them, then the bond between the both atoms is polar and will possess a dipole moment.

The direction of the dipole moment vector is always towards the negative atom as shown in the image attached. Only HF and IBr are polar. Diatomic molecules such as Br2 and F2 are nonpolar.