Which of the following carbonates undergoes decomposition upon heating?

Powdered Beryllium burns in air to give

Among the alkaline earth metals ($Be$,$Mg$,$Ca$,and $Sr$) of group $IIA$,which one forms an ionic chloride?

The setting of Plaster of Paris is associated with which of the following?

The correct order of melting point for alkaline earth metals is:

What happens when:
$(i)$ magnesium is burnt in air
$(ii)$ quick lime is heated with silica
$(iii)$ chlorine reacts with slaked lime
$(iv)$ calcium nitrate is heated?