Explanation:

Sodium, with an atomic number of 11, belongs to group 1A of the periodic table. It is a highly reactive metal and readily forms a +1 oxidation state by losing one electron to achieve a stable electron configuration similar to that of a noble gas (neon). However, sodium generally does not show an oxidation state of +2 due to its high second ionization potential.

High second ionization potential:
The second ionization potential is the energy required to remove a second electron from an atom or ion. In the case of sodium, the first ionization potential (energy required to remove the first electron) is relatively low, as it only needs to lose one electron to achieve a stable configuration. However, the second ionization potential, which involves removing a second electron, is significantly higher.

Explanation:
When sodium loses one electron, it forms a sodium ion (Na+), which has a stable electron configuration (2,8). To achieve a +2 oxidation state, sodium would need to lose another electron, resulting in a sodium ion with a 2+ charge (Na2+). However, removing a second electron from a sodium ion requires much more energy due to the increased electrostatic attraction between the remaining electrons and the positively charged nucleus.

Stability of the +1 oxidation state:
The +1 oxidation state of sodium is more stable than the +2 oxidation state due to the following reasons:

1. Electronegativity: Sodium has a relatively low electronegativity value, indicating that it has a low tendency to attract electrons towards itself. This makes it easier for sodium to lose one electron and form a stable +1 oxidation state.

2. Ionic radius: Sodium has a relatively large ionic radius, which means that the outermost electron is located far from the nucleus. This weakens the attraction between the nucleus and the electron, making it easier to remove.

3. Ionization potential: The first ionization potential of sodium is relatively low, meaning that it requires less energy to remove the first electron. This favors the formation of the +1 oxidation state.

In conclusion, sodium generally does not show an oxidation state of +2 because of its high second ionization potential, which makes it energetically unfavorable to remove a second electron. The +1 oxidation state is more stable due to factors such as low electronegativity, large ionic radius, and relatively low first ionization potential.