When comparing gallium (Ga) and bromine (Br), bromine has the more negative electron affinity. This means that bromine has a greater tendency to gain an electron compared to gallium.
Bromine is a halogen, and elements in this group are known for their high electronegativity and strong ability to attract electrons. When bromine gains an electron, it achieves a noble gas configuration, which is a stable arrangement. As a result, the process releases a significant amount of energy, leading to a highly negative electron affinity value.
On the other hand, gallium, being a metalloid, has a less negative electron affinity. Although gallium can also gain an electron, the energy released is not as high as that for bromine. This is due in part to the larger atomic size and the nature of the electron shell configuration of gallium.
To summarize, bromine not only has a more negative electron affinity but also exhibits a stronger drive toward gaining electrons when compared to gallium.