The treatment of an aqueous solution of \( 3.74 \ \mathrm{g} \) of \( \mathrm{Cu(NO_3)_2} \) with excess \( \mathrm{KI} \) results in a brown solution along with the formation of a precipitate. Passing \( \mathrm{H_2S} \) through this brown solution gives another precipitate \( X \). The amount of \( X \) (in \( \mathrm{g} \)) is _______.
\([ \text{Given : Atomic mass } \mathrm{H} = 1, \ \mathrm{N} = 14, \ \mathrm{O} = 16, \ \mathrm{S} = 32, \ \mathrm{K} = 39, \ \mathrm{Cu} = 63, \ \mathrm{I} = 127 ]\)
