At high temperature,nitrogen combines with $CaC_2$ to give:

Which of the following is not a monomer for a high molecular mass silicone polymer?

Assertion : $Pb^{4+}$ compounds are stronger oxidizing agents than $Sn^{4+}$ compounds.
Reason : The higher oxidation states for the group $14$ elements are more stable for the heavier members of the group due to 'inert pair effect'.

Match the species given in Column-$I$ with the properties mentioned in Column-$II$.

Column-$I$	Column-$II$
$A$. $BF_4^-$	$1$. Oxidation state of central atom is $+4$
$B$. $AlCl_3$	$2$. Strong oxidizing agent
$C$. $SnO$	$3$. Lewis acid
$D$. $PbO_2$	$4$. Can be further oxidized
	$5$. Tetrahedral shape

Which of the following non-metal elements has half the atomicity of sulfur?

Give one method for industrial preparation and one for laboratory preparation of $CO$ and $CO_2$ each.