Alkali metal ions are colourless as well as diamagnetic. Explain

The diamagnetic ion is

Diamagnetic ion is

Which ion is colourless:

Alkali metals are paramagnetic but their salts are dimagnetic. Explain.

Which of the following ions can form paramagnetic as well as diamagnetic complexes (without considering magnetic property of ligands)?

Which ion is colourless in water ?

Explain the following: a. Alkali metals are paramagnetic, but their salts are diamagnetic. b. The inside surface of a glass bottle containing caustic sada becomes dull.

Which of the ion is colourless?