Tests for cations & anions, gases & water

• what is the rythm for the 5 flame tests ?

  lying burnt in the yellow sun as the palms hit lilac lightning catching on orange-red fire counting the green flowers
• what is the test for lithium ions ?

  flame test, colour goes red
• what is the test for sodium ions?

  flame test, colour goes yellow
• what is the test for potassium ions ?

  flame test, colour goes lilac
• what is the test for calcium ions ?

  flame test, colour goes orange-red
• what is the test for copper ?

  flame test, colour goes blue-green
• what are the steps for carrying out a flame test ?

  • dip loop of wire into dilute HCI
  • hold in blue flame
  • dip loop of wire into sample
  • then place loop back into the flame
• what is the result of the hydroxide test for ammonium ?

  • ammonia gas produced
  • turns damp red litmus paper blue
• what is the result o the hydroxide test for copper ?

  • light blue precipitate formed
• what is the result of the hydroxide test for iron (II) ?

  • a green precipitate is formed
• what is the result of the hydroxide test for iron (III) ?

  • red-brown precipitate formed
• how do you test for carbonate ions (anions) ?

  1. add dilute acid
  2. bubble gas through limewater
  3. limewater turns cloudy if carbonate ions present
• how do you test for sulfate ions (anions) ?

  1. add dilute nitrate acid
  2. add barium nitrate solution
  3. white precipitate of barium nitrate formed if sulfate ions present
• how do you test for halide ions (anions) ?

  1. add dilute nitric acid
  2. add silver nitrate solution
• what are the positive results for each halide test?

  Chloride: White precipitate (silver chloride)

  Bromide: Cream precipitate (silver bromide)

  Iodide: Yellow precipitate (silver iodide)
• what are the 5 common gases tested ?

  1. chlorine
  2. oxygen
  3. carbon dioxide
  4. hydrogen
  5. ammonia
• what is the test for chlorine gas ?

  • bleach a damp blue litmus paper
  • will turn white if chlorine is present
• what is the test for oxygen gas ?

  • relights a glowing splint
• what is the text for carbon dioxide gas ?

  • bubble a gas through a test tube of limewater
  • limewater turns cloudy if carbon dioxide is present
• what is the test for hydrogen ?

  • makes a squeky pop with a lighted splint placed into the gas
• what is the test for ammonia gas ?

  • ammonia turns damp red litmus paper blue
  • has a strong smell
• what can be used to test for water ?

  copper (II) sulfate crystals
• how to test for water ?

  • copper (II) sulfate mixed with water creating blue crystals
  • heat the hydrated copper (II) sulfate crystals it drives the water away
  • left with a white anhydrous copper (II) sulfate powder
• what us the boiling and freezing point of water ?

  Boiling point: 100 degrees

  Freezing point: 0 degrees