When iron (II) sulfide was dissolved in excess of hydrochloric acid, 11.2 liters of gas were released. The mass of iron (II) sulfide is equal to

Compose a reaction equation
FeS + 2HCl = H2S + FeCl2
Calculate the amount of gas substance (H2S) 11.2 L / 22.4 L / mol = 0.5 mol
Calculate the amount of iron sulfide substance (2) (FeS) = 0.5 mol (equal to the amount of gas substance)
Calculate the mass of iron sulfide (2) m (FeS) = M * n (amount of substance) = 88 g / mol * 0.5 mol = 44 g

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