The kind of reaction that occur when aqueous solution of barium sulfide is mixed with sulfuric acid is PRECIPITATION REACTION. The equation for the chemical reaction is this: BaS + H2SO4 = BaSO4 + H2S. This equation shows that barium sulfide react with sulfuric acid to yield barium sulphate and hydrogen sulfide. During the reaction, a precipitate is formed and a gas is given off. The precipitate formed is barium sulphate and the gas that was given of is hydrogen sulphide.