The thermal stability increases down the group.

BeCO$_3$ is more thermally stable than MgCO$_3$ due to the high polarizing power of Be$^{2+}$

BaCO$_3$ decomposes at a much higher temperature than MgCO$_3$.

The decomposition of these carbonates yields the corresponding metal oxide and CO$_2$.

Paramagnetic

Diamagnetic

Ferromagnetic

All of these

Be < Mg < Ca < Sr

Be > Mg > Ca > Sr

Be < Mg > Ca < Sr

Sr < Ca < Mg < Be

${\rm{NaOH}}$

${\rm{Ca}}{\left( {{\rm{OH}}} \right)_2}$

${\rm{KOH}}$

${\rm{Ba}}{\left( {{\rm{OH}}} \right)_2}$

${{\rm{K}}_2}{\rm{O }}{\rm{. A}}{{\rm{l}}_2}{{\rm{O}}_3}.6{\rm{Si}}{{\rm{O}}_2}$

${\rm{KN}}{{\rm{O}}_3}$

${{\rm{K}}_2}{\rm{S}}{{\rm{O}}_4}{\rm{. MgS}}{{\rm{O}}_4}{\rm{. MgC}}{{\rm{l}}_2}.6{{\rm{H}}_2}{\rm{O}}$

${\rm{KCl }}{\rm{. MgC}}{{\rm{l}}_2}.6{{\rm{H}}_2}{\rm{O}}$

${{\rm{O}}_2}$

${\rm{OC}}{{\rm{l}}^ - }$

${\rm{C}}{{\rm{l}}_2}$

${\rm{C}}{{\rm{l}}^ - }$

${\rm{MgO}}$

${\rm{CaO}}$

${\rm{BaO}}$

${\rm{BeO}}$

${\rm{CaC}}{{\rm{O}}_3}{\rm{and CaO}}$

Slaked lime and water

Slaked lime, sand and water

None of the above

Calcium chloride

Sodium carbonate

Sodium chloride

Potassium nitrate

$K{O_2}$

$Ba{O_2}$

$Mn{O_2}$

$N{O_2}$

Bauxite

Malachite

Carnallite

Haematite