(b) - If the colour is already olive green, add the 0.01 M HCL solution one drop at a time until the solution's colour just turns purple and perform step (a).
6. - Connect the pear shaped flask with the adjusted hydrogen peroxide solution to the condenser arrangement (see fig 5 or fig 6).
9. - Connect the 100 ml round bottom flask with the acidified sample to the condenser arrangement (see fig 5 or fig 6)
10. - Make sure that all joints on the apparatus are secure and sealed by holding both joints and applying a slight pushing and twisting force (see safety note) and securing clamps and clips where indicated in fig 5 or fig 6 ( see problems with leaks)
10. - Secure and adjust the air bleed or bubbler tube so it sits a few millimeters from the bottom of the round bottom flask.
