chemical tests

• What gas is tested by a burning splint?

  Hydrogen
• What sound indicates the presence of hydrogen gas?

  A ‘squeaky pop’ sound
• How is oxygen tested in a laboratory?

  Using a glowing splint
• What happens to a glowing splint in oxygen?

  It relights
• What is the test for carbon dioxide gas?


  Bubble through limewater
• What indicates the presence of carbon dioxide in limewater?

  It turns milky
• What color change indicates ammonia gas presence?

  Damp red litmus turns blue
• What forms when ammonia reacts with hydrogen chloride gas?

  White smoke of ammonium chloride
• What happens to damp litmus paper in chlorine gas?

  It turns white
• What does a flame test indicate?

  The presence of a specific metal
• What color flame indicates lithium presence?

  Red
• What color flame indicates sodium presence?

  Yellow
• What color flame indicates potassium presence?

  Lilac
• What color flame indicates calcium presence?

  Orange-red
• What color flame indicates copper presence?

  Blue-green
• What happens when ammonia reacts with NaOH(aq)?

  It forms NH₃(g)
• What color precipitate does copper(II) produce with NaOH(aq)?


  Blue precipitate
• What color precipitate does iron(II) produce with NaOH(aq)?


  Green precipitate
• What color precipitate does iron(III) produce with NaOH(aq)?

  Brown precipitate
• What is the test for halide ions?

  Add dilute nitric acid and silver nitrate
• What precipitate does chloride ion produce with silver nitrate?

  White precipitate
• What precipitate does bromide ion produce with silver nitrate?

  Cream precipitate
• What precipitate does iodide ion produce with silver nitrate?

  Yellow precipitate
• What is the test for sulfate ions?

  Add dilute hydrochloric acid and barium chloride
• What indicates the presence of sulfate ions in barium chloride solution?

  A white precipitate forms
• What do carbonates react with to produce carbon dioxide?

  Dilute acids
• How can you identify carbon dioxide gas from carbonates?

  Bubble through limewater
• What happens to limewater when carbon dioxide is present?

  It goes cloudy
• What color is anhydrous copper(II) sulfate?

  White
• What color does anhydrous copper(II) sulfate turn when water is present?

  It turns blue
• How can you test the purity of water?

  By measuring its boiling point
• What is another method to test water purity?

  Evaporating it on an evaporating dish