A colourful challenge
Picture: © Gordon's School
Pupils from Gordon’s School – who previously brought you the 'Chemistree' grown from copper and silver nitrate crystals – have risen to a new challenge.
As part of the school’s program of academic enrichment, pupils from year 9 and year 10 joined forces to create a giant pH-indicator chart. Working in pairs, each pair made a different indicator from fruit and vegetables, including plum skin, turnip skin, red cabbage and raspberries. Pupils were able to decide whether to dissolve the indicator in ethanol or water and were given the freedom to experiment.
Several other attempts, such as indicators from kiwi and strawberry, were unsuccessful.
After making numerous different indicators, they created the giant chart, with pH labelled at the top and examples of each indicator down the side. The whole thing was completed in 2 hours.
"Pupils enjoyed the freedom to each create a different indicator, and simultaneously working as part of a team for a common goal", said chemistry teacher William Barron de Burgh.
From top to bottom, the indicators were made from: radish skin, plum skin, blueberry, turnip skin, redcurrant, lemon skin, apple skin, blackcurrant, beetroot, blackberry, methyl orange, bromomethyl blue, red cabbage, raspberry, phenolphthalein, universal indicators Picture: © Gordon's School