Question

Consider the group 1A elements sodium (period 3), potassium (period 4), and rubidium (period 5). What would you predict about the ionization energies of these elements?

Answer 1

Ionization energies increase from left to right and down to up in a periodic table. The given elements are all group one elements so the ionization energy could be rank as Rb>K>Na. Hope this answers the question. Have a nice day.

Answer 2

Answer: The order predicted would be: ionization energy of sodium > ionization energy of potassium > ionization energy of rubbidium.

Step-by-step explanation:

1) The ionization energy is the energy that has to be added to a gaseous atom to remove an electron and form a positive ion.

2) The ionization energy decreases when you move down a group.

3) The reason for this decrease of the ionization energy down a group is that, as you descend inside a group, the atom size increases, which implies that the valence electrons (the electrons in the outermost shell) are further away from the nucleus, and so less energy is needed to remove those electrons.