Question

this three dimensional version of the periodic table shows ionization energy trends. ionization energy is the energy required to remove a valence electron from a neutral, gaseous atom. ionization energy trends across periods are generally more consistent than electron affinity trends, although both are useful. use what you observe about ionization energy to explain why the halogens do not form positive ions. type your answer here.

Explanation:

Ionization energy is the energy needed to remove a valence electron. Halogens are in Group 17. They have high ionization energies. Removing a valence electron (to form a positive ion) would require a large amount of energy. Halogens tend to gain an electron (low electron - affinity energy) to achieve a full outer shell (noble - gas configuration) rather than lose one.

Answer:

Halogens have high ionization energies. The energy required to remove a valence electron (to form a positive ion) is too large. Instead, they gain an electron (lower energy process) to complete their outer shell. So, they do not form positive ions.