What is the result of adding barium chloride to sulfate ions?

Adding barium chloride to sulfate ions results in the formation of a white precipitate of barium sulfate.

When barium chloride (BaCl2) is added to a solution containing sulfate ions (SO4 2-), a chemical reaction occurs. This reaction is a type of precipitation reaction, which is a reaction that produces a solid, or precipitate, from a solution. The precipitate formed in this case is barium sulfate (BaSO4), which appears as a white solid.

The chemical equation for this reaction is:

BaCl2 (aq) + SO4 2- (aq) → BaSO4 (s) + 2Cl- (aq)

In this equation, the (aq) notation indicates that the substances are dissolved in water, while the (s) notation indicates a solid. The arrow indicates the direction of the reaction, from reactants to products.

The formation of the white precipitate of barium sulfate is a key visual indicator of the presence of sulfate ions in a solution. This is a common test in analytical chemistry, known as the barium chloride test for sulfates. If the white precipitate forms, it confirms the presence of sulfate ions in the solution.

The reaction between barium chloride and sulfate ions is also an example of a double displacement reaction, or metathesis reaction. In this type of reaction, the cations and anions of two different compounds switch places to form two new compounds. In this case, the barium cation (Ba2+) from barium chloride and the sulfate anion (SO4 2-) from the sulfate ion solution combine to form barium sulfate, while the chloride anions (Cl-) remain in solution.