On heating, LiNO₃ gives how many compounds among the following __________
Li₂O,N₂,O₂,LiNO₂,NO₂

Solution

Chemistry ma’am · 3 steps

Lithium behaves like magnesium, not sodium: its nitrate breaks down all the way to the oxide.

1. Why lithium differs. The Li⁺ ion is very small, so it has high polarising power. It distorts the large nitrate ion and pulls it apart completely. This is the diagonal relationship with magnesium, whose nitrate also gives the oxide.

   4LiNO₃ →(Δ) 2Li₂O + 4NO₂ + O₂

2. Check the list. From the five given, Li₂O, NO₂ and O₂ form. No N₂ forms, and LiNO₂ does not form, because that product belongs to NaNO₃ and KNO₃.
3. So. Heating LiNO₃ gives 3 of the listed species.

The common slip: 2. Treating LiNO₃ like NaNO₃ gives only LiNO₂ and O₂, which is 2, not 3.

The idea to keep. LiNO₃ decomposes like Mg(NO₃)₂ to oxide, NO₂ and O₂. Other alkali metal nitrates stop at the nitrite and give only O₂.

Answer from the NTA final answer key. Solution by PrepWiser.