Upon mixing $Cu(N{O}_3{)}_2*3H_{2}O(1mM)$ with $N{a}_2{S}_2{O}_3*5H_{2}O(2mM),$ and heating at $180C,$ pure CuS was produced. However, upon taking $6mM$ of $N{a}_2{S}_2{O}_3,$ CuS along with $S$ was obtained. Answer following

$($a$)$ What thermogram is shown in the right side figure $?[1]$

$($b$)$ In case of pure CuS $($curve a$),$ write the possible products after first mass loss of $12\%($upon heating to $-380C$ in oxygen$/$air$)$ with reason.

$[3]$

$($c$)$ Why there was a larger mass loss in curve b$?$

$[1]$

$($d$)$ After the first mass loss, there are three mass gains $($region II$,$ III and IV$)$ and one mass loss $($above $700C).$ What possibie products are expected and how would you confirm those.

$[3]$

$($e$)$ Schematically draw TG curves for $($i$)$ boiling in a crucible with a small hole in the lid and $($ii$)$ sublimation in a crucible without a lid.

$[2]$