Explain in terns of atomic structure why barium has a lower first ionization energy than magnesium.

Barium and magnesium are two elements which belong to the same group, group 2A. This means that the two elements have two valence electrons in their outer shell.

The difference is, however, since barium is lower in group than magnesium, it has more electron shells than magnesium and, therefore, its radius is greater. The attraction force between the nucleus and the valence electrons in barium is lower as a result, as force is inversely proportional to distance. Hence, a lower amount of energy is required to remove the valence electrons from barium.

priyankatutor priyankatutor · Answer 2 · 2021-11-18T15:15:57+01:00

Ionization energy is minimum energy that is required to take out valence electron from atom or molecule. The ionization energy of the barium is lower than the magnesium.

Ionization energy:

It is the minimum amount of energy that is required to take out the most loosely bonded electron from an atom. It is measured in Electron volts.

Barium:

Atomic number of the Barium is 56.

The valence electron of is present 6th shell.
Hence, the distance between nucleus and valence shell is more.
Therefore, it is easier to take out electrons from valence shell of Barium.

Magnesium:

The atomic number of Magnesium is 12.
The valence electron present in the 2nd shell.
So, valence shell is closer to the nucleus.
Hence, It needs more energy to take out electrons from the valence shell of magnesium.

Therefore, the ionization energy of the barium is lower than the magnesium.

To know more about ionization energy, refer to the link:

https://brainly.com/question/2571722