What describes a molecule in which the positive and negative charges are separated?
Dipole
A molecule in which the positive and negative charges are separated is called a dipole. The separation of charges can occur due to differences in electronegativity between the atoms in the molecule, resulting in an uneven distribution of electron density.
To determine if a molecule is a dipole, you need to consider the polarity of the individual bonds and the molecular geometry. A polar bond is formed when two atoms have a significant difference in electronegativity. The more electronegative atom attracts the shared electrons more strongly, creating a partial negative charge (δ-) on that atom and a corresponding partial positive charge (δ+) on the other atom.
If a molecule has polar bonds and an asymmetric molecular shape, the dipole moments of the individual bonds may not cancel out, resulting in an overall dipole moment for the molecule. On the other hand, if a molecule has polar bonds but a symmetric molecular shape, the dipole moments of the individual bonds may cancel out, making the molecule nonpolar.
So, to determine if a molecule is a dipole, you would need to analyze the electronegativity of its atoms and consider its molecular geometry. Experimental techniques like measuring dipole moments or using spectroscopy can also provide evidence for the existence of dipoles in molecules.