why is nh3polar but bacl2 non polar
NH3 (Ammonia) is a polar molecule because it has a central nitrogen atom that forms three bonds with three hydrogen atoms. The nitrogen atom also has a lone pair of electrons, which creates a region of negative charge around the nitrogen atom. The three hydrogen atoms form a pyramidal shape around the nitrogen atom, resulting in an unequal distribution of charge in the molecule.
To determine why NH3 is polar, we can look at the electronegativity difference between nitrogen and hydrogen. Nitrogen has a higher electronegativity than hydrogen, which means it has a greater ability to attract electrons towards itself. As a result, the nitrogen atom in NH3 attracts the shared electrons more strongly, creating a partial negative charge around the nitrogen atom, and leaving the hydrogen atoms with a partial positive charge. This charge imbalance gives the NH3 molecule a net dipole moment, making it polar.
On the other hand, BaCl2 (Barium chloride) is a nonpolar molecule because the electronegativity difference between barium and chlorine is very small. Barium is a metal with a low electronegativity, while chlorine is a nonmetal with a higher electronegativity. As a result, the chlorine atoms do have a greater attraction for electrons, but the difference is not large enough to create significant charge imbalances.
In BaCl2, the barium atom forms two bonds with two chlorine atoms, resulting in a linear molecule. Since the electronegativity difference between barium and chlorine is small, the shared electrons are nearly equally attracted to both atoms. This results in no significant charge separation along the molecule, and therefore BaCl2 is considered nonpolar.
Understanding the electronegativity difference and the molecular geometry of the atoms involved is crucial to determining the polarity of a molecule.