Which of the following carbonates decomposes to the oxide and CO2 on moderate heating, whereas the carbonates of the other alkali metals are thermally stable?

NEET levelSingle correct optionDifficulty 1 of 3sb046

Which of the following carbonates decomposes to the oxide and $CO X_{2}$ on moderate heating, whereas the carbonates of the other alkali metals are thermally stable?

The small

Li X^{+}

ion polarises the carbonate ion strongly and forms the very stable

Li X_{2} O

. So

Li X_{2} CO X_{3} Li X_{2} O + CO X_{2}

occurs on heating, while the carbonates of Na to Cs are stable.