1
$\begingroup$

I have a doubt about decomposition of alkali metals. Why does $\ce{LiNO3}$ decompose to give $\ce{Li2O}$ and $\ce{NO2}$ where as other alkali metals decompose to give corresponding nitrite and oxygen?

$\endgroup$
4
$\begingroup$

Have you checked Wikipedia?

Upon thermal decomposition, $\ce{LiNO3}$ gives lithium oxide ($\ce{Li2O}$), nitrogen dioxide, and oxygen:

$$\ce{4 LiNO3 → 2 Li2O + 4 NO2 + O2}$$

Other group I nitrates decompose differently, forming the nitrite salt and oxygen. Because of its relatively small size, the lithium cation is very polarizing, which favors the formation of the oxide.

$\endgroup$
3
$\begingroup$

You actually can get lithium nitrite from the nitrate by controlling the decomposition temperature around 500°C. But yes, as Nilay points out the nitrite is more prone to decomposing further than sodium nitrite because of the polarizing power of the lithium cation.

$\endgroup$

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.