The element having atomic number $56$ belongs to

The incorrect order of solubility in water is

The number of electrons in the valence shell of calcium is

Which of the following sets represents the alkaline earth metals?

Out of the following elements,which one do you expect to be most reactive chemically?

Choose the correct statement from the following:
$(i)$ Beryllium is not readily attacked by acids because of the presence of an oxide film on the surface of the metal.
$(ii)$ $BeO$ is an amphoteric oxide.
$(iii)$ Beryllium exhibits coordination number more than four.
$(iv)$ Beryllium oxide is purely acidic in nature.