Which group will show lowest second ionization energy ? (Non radioactiv element)

Answer

To determine which group will show the lowest second ionization energy among non-radioactive elements, we can follow these steps:

### Step 1: Understand Ionization Energy
Ionization energy is defined as the energy required to remove an electron from an atom in its gaseous state. The second ionization energy refers to the energy required to remove a second electron after the first one has already been removed.

**Hint:** Remember that ionization energy increases as you remove more electrons because the remaining electrons are held more tightly by the nucleus.

### Step 2: Identify Groups with Electrons in the Outermost Shell
Elements in the periodic table are organized into groups based on their electron configurations. The group number indicates how many electrons are in the outermost shell (valence electrons). For example, Group 1 has one valence electron, and Group 2 has two valence electrons.

**Hint:** Groups with fewer valence electrons tend to have lower ionization energies because they are more willing to lose electrons.

### Step 3: Analyze Group 2 Elements
Group 2 elements, also known as alkaline earth metals, have two electrons in their outermost shell. When the first electron is removed, the remaining electron achieves a stable configuration similar to that of noble gases. This means that the second ionization energy will be relatively low because the atom becomes more stable after losing the second electron.

**Hint:** Consider how the stability of the resulting ion affects the energy required for further ionization.

### Step 4: Compare with Other Groups
While analyzing other groups, we find that:
- Group 1 (alkali metals) has one valence electron, so the second ionization energy is not applicable as they only have one electron to remove.
- Group 13 has three valence electrons, and removing the second electron from these elements requires more energy than from Group 2.
- Group 17 (halogens) has seven valence electrons, and removing a second electron would require even more energy due to the increased nuclear charge.

**Hint:** Compare the stability and electron configurations of the ions formed when electrons are removed from different groups.

### Step 5: Conclusion
Based on the analysis, Group 2 elements (alkaline earth metals) will show the lowest second ionization energy among non-radioactive elements because the removal of the second electron leads to a stable noble gas configuration.

**Final Answer:** Group 2 (alkaline earth metals) will show the lowest second ionization energy.