Final answer:
A molecule with partially charged positive and negative areas is a polar molecule, resulting from the asymmetrical distribution of electron density, which creates a dipole with opposite charged regions.
Step-by-step explanation:
A molecule that has partially charged positive and negative areas is known as a polar molecule. This occurs due to an asymmetrical distribution of charges within the molecule, where one end possesses a slight positive charge (often represented as δ+) and the other a slight negative charge (δ-). The classic example of a polar molecule is water (H2O), which has a bent shape causing the oxygen end to be more negative and the hydrogen ends to be more positive, thus creating a dipole moment across the molecule. Another example is hydrogen fluoride (HF), which also contains a polar covalent bond. In such molecules, the polarization arises due to the unequal sharing of electrons between atoms, leading to a separation of charged poles, similar to the north and south poles of a magnet.