How To Test For Negative Ions

The video tutorial explains how to test for carbonate, sulfate, and nitrate ions. For carbonates, dilute acid is added, and the gas produced is bubbled through lime water, turning it milky if carbonates are present. Sulfates are tested by adding barium chloride, forming a white precipitate. Nitrates are tested by adding sodium hydroxide and aluminum powder, producing ammonia, which turns damp litmus paper blue. The video emphasizes writing balanced chemical equations for these reactions.

What happens to litmus paper when ammonia is present?

Explain the significance of a white precipitate formed when testing for sulfates.