Question

Which is the strongest base Cl or Br ?

Answer 1

• A base is a substance that can donate pair of electrons or accept protons to form a bond.
• Types of Lewis bases :

1. Neutral bases containing a central atom with lone pair of electrons, e.g., : NH₃, R :NH_{2, ,} etc.
2. Anions or negatively charged ions, e.g., F^-, Cl^- , Br^- , etc.

• A strong conjugate base has weaker acids and a weaker conjugate base has stronger acids.
• The acidity trend in halogens in increasing order F < Cl < Br < I because the bond enthalpy decreases down the group thus more easily the halide- hydrogen bond will break.
• clearly, Br is more acidic than Cl. Therefore, Cl is a strong base than Br.