hydrochloric acid combing with zinc forms hydrogen gas
zinc_hydroxide is not ionic_compound. zinc_hydroxide is ionic_compound. hydrochloric_acid is acid. zinc_hydroxide is not chemical_compound. zinc_hydroxide is not crystal. zinc_hydroxide is electrolyte. hydrochloric_acid is not acid. zinc_hydroxide is crystal. zinc_hydroxide is chemical_compound. zinc_hydroxide is inorganic_compound.