In a polar bond, the more electronegative atom is the negative side.. True False
The correct answer and explanation is :
Correct Answer: True
In a polar bond, the more electronegative atom is the negative side of the bond. This is because electronegativity is the ability of an atom to attract shared electrons in a chemical bond. When two atoms with different electronegativities form a covalent bond, the electrons are not shared equally. Instead, they are pulled closer to the more electronegative atom, creating a partial negative charge (δ⁻) on that atom and a partial positive charge (δ⁺) on the less electronegative atom.
For example, in a water (H₂O) molecule, oxygen is more electronegative than hydrogen. This causes the oxygen atom to pull the shared electrons closer to itself, making oxygen partially negative (δ⁻) and hydrogen partially positive (δ⁺). This uneven distribution of charge makes the O-H bonds polar.
Another example is the hydrogen chloride (HCl) molecule. Chlorine is more electronegative than hydrogen, so the electron density is pulled toward chlorine, giving it a partial negative charge (δ⁻), while hydrogen has a partial positive charge (δ⁺).
The polarity of a bond depends on the difference in electronegativity between the two atoms. If the difference is significant (generally greater than 0.5 on the Pauling scale), the bond is considered polar. If the difference is very large (greater than 1.7), the bond is often considered ionic rather than covalent.
Polar bonds contribute to the overall polarity of molecules, which affects properties like solubility, boiling point, and intermolecular interactions. Polar molecules, such as water, can dissolve other polar substances, whereas nonpolar molecules, like oil, do not mix well with polar substances.
Thus, it is true that in a polar bond, the more electronegative atom is the negative side due to its stronger pull on the shared electrons.