Which of the following alkaline earth metals is the most electropositive?

Which one of the following alkaline earth metals does not form hydride when it is heated with hydrogen directly?

The thermal stability of alkaline earth metal carbonates $MgCO_3$,$CaCO_3$,$BaCO_3$,and $SrCO_3$ decreases as:

Which of the following ions forms a hydroxide that is readily soluble in water?

Plaster of Paris is used:

How would you explain the following observations?
$(i)$ $BeO$ is almost insoluble but $BeSO_4$ is soluble in water,
$(ii)$ $BaO$ is soluble but $BaSO_4$ is insoluble in water,
$(iii)$ $LiI$ is more soluble than $KI$ in ethanol.