Question 1: Define a sulfate ion and write its chemical formula.

Answer: A sulfate ion is a polyatomic anion with the chemical formula SO₄²⁻.

Question 2: Explain the principle behind testing for sulfates using barium chloride solution.

Answer: Barium chloride reacts with sulfate ions to form a insoluble barium sulfate precipitate, indicating the presence of sulfates.

Question 3: What is the chemical formula of barium sulfate, and what is its significance in sulfate tests?

Answer: BaSO₄; it is the insoluble precipitate formed during sulfate testing, confirming the presence of sulfate ions.

Question 1: Calculate the mass of barium sulfate (BaSO₄) formed when 50 mL of a 0.02 M barium chloride solution reacts completely with sulfate ions.

Answer: Mass = moles × molar mass = (0.02 mol/L × 0.050 L) × 233.39 g/mol ≈ 0.233 g

Question 1: Describe the step-by-step procedure to test a water sample for sulfates using barium chloride solution.

Answer: First, collect a small sample of the water. Add a few drops of dilute hydrochloric acid to remove carbonate impurities. Then, add a few drops of barium chloride solution. Observe if a white precipitate of barium sulfate forms, indicating the presence of sulfates. Ensure proper disposal of chemicals and wear protective gloves and goggles.

Question 2: Identify two safety precautions students should follow during sulfate testing in the laboratory.

Answer: Wear protective gloves and goggles, and handle chemicals carefully to avoid spills and contact.

Question 1: A sample of industrial wastewater tested positive for sulfates, producing a dense white precipitate when tested with barium chloride. What does this suggest about the composition of the wastewater?

Answer: It indicates that the wastewater contains sulfate ions, which can originate from industrial processes or pollutants.

Question 1: Explain why barium sulfate is used in sulfate tests instead of other barium compounds.

Answer: Barium sulfate is used because it is insoluble in water, making it easy to identify as a precipitate. Other barium compounds, like barium chloride, are soluble and would not produce a visible precipitate for detection.

Question 2: A water sample shows no precipitate when tested with barium chloride solution. What can you conclude about the sulfate content in the sample?

Answer: The sample likely does not contain sulfate ions, or the sulfate concentration is below the detection limit.

Question 1: Discuss how sulfate testing is important in environmental monitoring and pollution control.

Answer: Sulfate testing helps detect pollution from industrial waste, ensuring water safety, and helps in maintaining environmental standards by monitoring sulfate levels in natural water sources.