The ionization energy refers to the energy required to remove an electron from an atom or ion in its gaseous state. In this case, we are comparing the ionization energies of beryllium (Be) and sodium ion (Na+).
Beryllium (Be) is an atom with a neutral charge, while sodium ion (Na+) has a +1 charge, indicating that it has lost one electron compared to a neutral sodium atom (Na). The ionization energy generally increases as you move from left to right across a period in the periodic table and decreases as you move down a group.
In the case of beryllium, it is located to the left of sodium in the second period of the periodic table, and it has a smaller atomic number. Therefore, beryllium has a higher ionization energy compared to sodium. Removing an electron from a smaller atom like beryllium requires more energy because the electron is closer to the positively charged nucleus and more strongly attracted to it.
In contrast, the sodium ion (Na+) has already lost one electron compared to neutral sodium (Na). As a result, the removal of another electron from the sodium ion would require less energy compared to removing the first electron from beryllium. Therefore, the sodium ion (Na+) would have a lower ionization energy compared to beryllium (Be).
In summary, beryllium (Be) has a higher ionization energy compared to the sodium ion (Na+).