The incorrect statement is option A: Mg cannot form complexes.

Explanation:
Complexes are formed when a metal ion interacts with one or more ligands to form a coordination compound. Ligands are typically Lewis bases that donate electron pairs to the metal ion.

Mg is a transition metal and can form complexes. It has a valence shell configuration of 3s^2 3p^6 3d^0, with two valence electrons in the 3s orbital. These electrons can be donated to ligands, forming coordinate covalent bonds.

The formation of complexes depends on several factors, including the size of the metal ion and the charge density.

- Be can form complexes due to a very small atomic size:
Be is a small atom with a high charge density, which allows it to form complexes. The small size of Be makes it suitable for complex formation as the ligands can approach the metal ion more closely, resulting in stronger electrostatic interactions.

- The first ionization potential of Be is higher than that of Mg:
The first ionization potential is the energy required to remove the first electron from an atom. The ionization potential of Be is higher than that of Mg because Be has a smaller atomic size and a greater nuclear charge, resulting in a stronger attraction between the valence electrons and the nucleus. This higher ionization potential indicates that Be is less likely to form complexes compared to Mg.

- Mg forms an alkaline hydroxide while Be forms amphoteric oxides:
Mg and Be have different chemical properties. Mg reacts with water to form an alkaline hydroxide, Mg(OH)2, which is a base. On the other hand, Be forms amphoteric oxides, such as BeO, which can react with both acids and bases.

- Mg cannot form complexes:
This statement is incorrect. Mg can form complexes. The formation of complexes depends on the size, charge, and electronic configuration of the metal ion. Mg has a stable electronic configuration with two valence electrons in the 3s orbital, which can be donated to ligands to form complexes.

Can you give an example of comple of Be..