Which of the following correctly explains the anomalous thermal instability of Lithium carbonate () — s Block Elements Chemistry Question

💡 Solution & Explanation

Lithium is very small in size and has high polarizing power (Fajans' rules). It polarizes the large, polyatomic carbonate anion ($CO_3^{2-}$), weakening the C-O bond and facilitating decomposition into a highly stable $Li_2O$ lattice and $CO_2$ gas upon heating.