When dissolving iron (II) sulfide in excess of hydrochloric acid, 2.24 L of gas was 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) 2.24 L / 22.4 L / mol = 0.1 mol
Calculate the amount of iron sulfide substance (2) (FeS) = 0.1 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 * 0.1 mol = 8.8 g

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