Cabbage

Cabbage pH Indicator Experiment

Aim: To extract natural pH indicator from the Purple Cabbage and use it to find the colour changes when the two concentrations of HCl, distilled water and NaOH
Hypothesis: I predict that the purple cabbage extract will indicate that the HCl 1m and HCl 0.01m are acidic solutions, that the distilled water is neutral and that NaOH is basic because it has a special chemical inside it which detects pH, then changes colour in response to it.
Materials:
-250mL Beaker                 -Dropper                           -Tweezers                       -Hydrochloric Acid 0.01m(HCl)
-100mL Beaker                 -Heatproof mat               -Safety Mitts                   -Hydrochloric Acid 1.0m(HCl)
-Bunsen burner               -Purple cabbage leaf     -Measuring Cylinder       -Sodium Hydroxide (NaOH)
-Gauze Mat                       -Matchbox                       -Funnel                             -Distilled Water
-Tripod                               -Stirring Rod                   -Filer Paper                       -8 Test tubes
-Test Tube Rack

Method:
Part 1
  1. Collect materials listed above, then set up a Bunsen burner.
  2. Fill a 250mL beaker with 150mL of distilled water, then tear up a purple cabbage leaf and place pieces in the filled beaker.
  3. Place the beaker above the Bunsen Burner on the tripod, and turn it on.   Keep boiling until water turns purple and slightly bubbling (approx. 10 minutes).
  4. Carefully remove the hot beaker from the Bunsen burner using the safety mitts, then placing it on the heatproof mat.
  5. When beaker is cool enough to be handled, strain the contents of the beaker using the funnel and filter paper into the 100mL beaker, then disposing of the leaves.

Part 2
  1. To determine the pH level of each labelled liquid, start by adding 5 drops of a chosen labelled substance into 1 test tube.
  2. Then use the dropper to collect some of the purple cabbage...