The correct order of the solubility of alkaline earth metal sulphates in water is

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

Among the metals $Be$,$Mg$,$Ca$,and $Sr$ of group $IIA$,which one forms the least ionic chloride in the periodic table?

State True or False:
$(1)$ $90 \ g \ Na$ and $170 \ g \ K$ are present in a person with $70 \ kg$ of body weight.
$(2)$ Ionization enthalpy of alkaline earth metals increases on moving top to bottom.
$(3)$ In vapour phase,$BeCl_2$ possesses a polymer-like arrangement.
$(4)$ $CaCO_3$ is used in the preparation of mortar.

Which of the following reactions does not take place?

Correct order of density in $IIA$ group (alkaline earth metals) is: