1_Testing for Positive and Negative Ions

1_Testing for Positive and Negative Ions

1. Positive

   • Flame Test
     • By Heating up the compound, it will glow a different colour depending on the Metal Positive Ion
     • Colours
       • Sodium
         • Yellow
       • Calcium
         • Brick Red
       • Lithium
         • Red (Crimson)
       • Potassium
         • Purple (Lilac)
       • Barium
         • Green
   • Adding Sodium Hydroxide
     • By adding Sodium Hydroxide to the solution, a precipitate forms
     • Make sure Compound is a Solution
     • Coloured Precipitate
       • Copper 2+
         • Blue
       • Iron 2+
         • Green
       • Iron 3+
         • Brown
     • White Precipitate
       • Calcium
         • Flame Test
           • Brick Red
       • Magnesium
         • Flame Test
           • Nothing
       • Aluminium
         • Add Excess
           • Precipitate will dissolve in excess

2. Negative

   • Testing For Carbonates
     • 1) React With An Acid
     • 2) Carbon Dioxide should be produced
     • 3) Bubble it through Lime Water
       • Go from Colourless to Cloudy
   • Halides
     • 1) Add Silver Nitrate
     • 2) Add Nitric Acid
     • 3) Look for colours
       • Chlorine
         • White
       • Bromine
         • Cream
       • Iodine
         • Yellow
   • Sulphates
     • 1) Add Barium Chloride
     • 2) Add Hydrochloric Acid
     • A white precipitate will be formed after