Tests for Gases and Anions

• What are practical tests for gases and anions?

  Tests for gases and anions
• What type of tests are mentioned in the material?

  Practical tests for gases and anions
• How many common gases are there tests for?

  Four common gases
• What are the tests for the four common gases?

  1. Chlorine: Bleaches damp litmus paper white.
  2. Oxygen: Relights a glowing splint.
  3. Carbon dioxide: Turns limewater cloudy.
  4. Hydrogen: Produces a 'pop' sound with a lit splint.
• What happens when chlorine bleaches damp litmus paper?

  It turns the paper white
• What does oxygen do to a glowing splint?

  Relights the glowing splint
• What is the result of carbon dioxide in limewater?

  It turns limewater cloudy
• What sound does hydrogen produce with a lit splint?

  'Pop' sound
• What happens when chlorine is mixed with damp litmus paper?

  It bleaches the paper white
• What should you do to test for oxygen in a test tube?

  Insert a glowing splint
• How can you identify carbon dioxide in a solution?

  By adding limewater and observing cloudiness
• What is the chemical reaction for sodium carbonate and hydrochloric acid?

  Na₂CO₃(aq) + 2HCl(aq) → CO₂(g) + 2NaCl(aq) + H₂O(l)
• What is the test for sulfates?

  Use hydrochloric acid and barium chloride
• How can you identify sulfate ions?

  By adding barium chloride to the solution
• What should you do to test for carbonate ions?

  Add dilute acid and observe bubbling
• What indicates the presence of carbonate ions in a solution?

  Bubbling when dilute acid is added
• What is the role of hydrochloric acid in testing for sulfates?

  It helps to precipitate barium sulfate
• What is the formula for sulfate ions?

  SO₄²⁻
• How do you test for anions in a mystery solution?

  Use dropping pipette to add dilute acid
• What happens when you add dilute hydrochloric acid to a carbonate?

  It produces carbon dioxide gas
• What is the expected outcome when testing for sulfates with barium chloride?

  Formation of a white precipitate
• What is the chemical formula for barium chloride?

  BaCl₂
• How do you confirm the presence of sulfate ions in a solution?

  Add barium chloride and look for precipitate
• What indicates the presence of carbonate ions when testing?

  Bubbling due to carbon dioxide release
• What is the purpose of using a dropping pipette in tests?

  To add small amounts of solution accurately
• What is the result of adding dilute acid to a carbonate?

  It produces bubbles of carbon dioxide
• How can you test for the presence of anions in a solution?

  By adding dilute acid and observing reactions
• What is the significance of observing a 'pop' sound in hydrogen testing?

  It confirms the presence of hydrogen gas
• What does the cloudiness in limewater indicate?

  Presence of carbon dioxide gas
• What is the chemical formula for carbon dioxide?


  CO₂
• What should you do if you suspect a solution contains sulfate ions?

  Add barium chloride to test
• How do you determine if a solution contains carbonate ions?

  By adding dilute acid and observing bubbling
• What is the expected result when testing for sulfates with barium chloride?

  Formation of a white precipitate
• What is the chemical formula for barium sulfate?

  BaSO₄
• How do you test for the presence of carbonate ions in a solution?

  Add dilute acid and observe for bubbles
• What indicates the presence of sulfate ions in a solution?

  White precipitate with barium chloride
• What is the role of hydrochloric acid in sulfate testing?

  It helps to precipitate barium sulfate
• What is the formula for carbonate ions?


  CO₃²⁻
• How do you confirm the presence of carbonate ions in a solution?

  Add dilute acid and look for bubbling
• What happens when you add dilute hydrochloric acid to a carbonate?

  It produces carbon dioxide gas