Chemistry - Complete s-block Question with Solution | TestHub

(i) More be the ionic nature, more be the attractive force between the species.

(ii) More be the attractive force, More be the thermal stability.

(iii) Ionic character for the same anionic species, increases down the group.

Thus, correct order for thermal-stability is

$\text{B}\text{a}\text{C}{\text{O}}_3>\text{C}\text{a}\text{C}{\text{O}}_3>\text{M}\text{g}\text{C}{\text{O}}_3$