Which of the following best explains the cause of dipole-dipole interactions between molecules?

• A. The attraction between the positive end of one polar molecule and the negative end of another polar molecule
• B. The attraction between ions and polar molecules
• C. The sharing of electrons between atoms in a molecule
• D. The instantaneous formation of temporary dipoles in nonpolar molecules

Answer: (A)

Verified step by step guidance

1. Understand that dipole-dipole interactions occur between polar molecules, which have permanent dipoles due to uneven distribution of electron density.
2. Recall that a polar molecule has a partial positive charge on one end and a partial negative charge on the other end, creating a permanent dipole moment.
3. Recognize that dipole-dipole interactions arise because the positive end of one polar molecule is attracted to the negative end of another polar molecule.
4. Differentiate dipole-dipole interactions from other types of intermolecular forces, such as ion-dipole interactions (between ions and polar molecules), covalent bonding (sharing electrons within molecules), and London dispersion forces (temporary dipoles in nonpolar molecules).
5. Conclude that the best explanation for dipole-dipole interactions is the attraction between the positive end of one polar molecule and the negative end of another polar molecule.