What is produced when $Mg$ burns in $CO_2$?

Which compounds are found as impurities in impure sodium chloride?

Given below are two statements:
Statement $I$: Lithium and Magnesium do not form superoxide.
Statement $II$: The ionic radius of $Li^{+}$ is larger than the ionic radius of $Mg^{2+}$.
In the light of the above statements,choose the most appropriate answer from the options given below:

Match the List-$I$ with List-$II$.

List-$I$ (Metal)	List-$II$ (Emitted light wavelength $(nm)$)
$A. Li$	$I. 670.8$
$B. Na$	$II. 589.2$
$C. Rb$	$III. 780.0$
$D. Cs$	$IV. 455.5$

Choose the most appropriate answer from the options given below:

Select the $INCORRECT$ statement regarding the solution of an alkali metal in liquid $NH_3$?

In the Solvay process,can we obtain sodium carbonate directly by treating the solution containing $(NH_4)_2CO_3$ with sodium chloride? Explain.