The elements of which group in the periodic table release the most energy by gaining an electron?

The elements of which group in the periodic table absorb the most energy when gaining an electron?

You look at the electron affinity (EA). The ones with the highest negative value release the most energy; the ones with the lowest negative value absorb the most energy.

The elements in Group 17 of the periodic table, also known as the Halogens, release the most energy when gaining an electron. This is because they have a high electron affinity and a strong tendency to attract an additional electron to complete their outermost energy level.

On the other hand, the elements in Group 1 of the periodic table, known as the Alkali Metals, absorb the most energy when gaining an electron. This is due to their low electron affinity and their tendency to lose an electron in order to achieve a stable electron configuration.

To determine which elements release or absorb the most energy when gaining an electron, you need to consider their positions in the periodic table. Specifically, you should look at the element groups and their electron configuration patterns.

1. Elements in Group 1 (Alkali Metals): These elements are found in the far left side of the periodic table. They have one valence electron in their outermost energy level. When they gain an electron, they must overcome significant electrostatic repulsion as the added electron experiences repulsive forces from the existing outermost electron. Hence, alkali metals release the most energy when gaining an electron.

2. Elements in Group 17 (Halogens): These elements are located in the second-to-last column on the right side of the periodic table. They have seven valence electrons in their outermost energy level and are only one electron short of having a complete electron configuration. As a result, halogens tend to strongly attract an additional electron to fill their outer energy level, requiring a significant amount of energy. Therefore, Group 17 elements absorb the most energy when gaining an electron.

It's important to note that while the general trend mentioned above applies, there may be specific exceptions and variations within certain elements or subgroups. Nonetheless, understanding the periodic table's organization helps identify trends in energy release or absorption during electron acquisition.