Answer : The correct option is, (C) \(H_2S\) gas
Explanation :
Double replacement reaction : It is a type of chemical reaction in which a positive cation and a negative anion of two reactants exchange their places to form two new products.
It is represented as,
\(XY+AB\rightarrow XB+AY\)
(X and A are the cations, Y and B are the anions)
When the iron sulfide (FeS) combined with hydrogen chloride (HCl) to give iron(II)chloride and hydrogen sulfide gas as a product.
The balanced chemical reaction will be,
\(FeS(s)+HCl(l)\rightarrow FeCl_2(s)+H_2S(g)\)
Hence, the gas would be, (C) \(H_2S\) gas
