Calculate the energy of an electron in the n = 2 level of a hydrogen atom.

The energy of an electron in the n = 2 level of a hydrogen atom is 3.40 eV.

Explanation:

Given: n = 2

The relation between energy and orbit of an atom is as follows.

Substitute the values into above formula as follows.

The negative sign indicates that energy is being released.

Thus, we can conclude that the energy of an electron in the n = 2 level of a hydrogen atom is 3.40 eV.

answer:

technetium is the most reactive. this is followed by silver. the least reactive out of these three elements is strontium.