Indigo is an organic compound that is found in three differently coloured forms – indigo itself, which is blue purple mono-bromoindigo and red-purple di-bromoindigo (figure 1). All about indigo Figure 1: Structures of indigo The experiment is also relevant to the use of science in industry and could be used as part of a project on this topic. More advanced organic chemistry students (ages 16+) could investigate the compounds and reactions more thoroughly. Younger students (ages 11-15) could simply do the extraction without going into much detail about the chemical reaction. Using basic lab equipment, secondary students of all ages could carry out this extraction in one or two practical sessions. This activity allows your students to follow in the footsteps of these early chemists, extracting indigo from the leaves of the woad plant. Thanks to Roman naturalist Pliny the Elder (see box on Pliny the Elder), we even know the dyeing methods used by ancient civilisations. The vivid purple of the Pharaoh’s sail was achieved using indigo – a natural dye that can be extracted from certain plants and animals. Until the advent of synthetic dyes 100 years ago, natural dyes (from plant, animal or mineral sources) were the only way to colour fabrics. This is because they are difficult and expensive colours to achieve using natural dyes. It belonged to the Pharaoh and was a vibrant and powerful sign to other Nile users that they should move aside to let the royal boat pass.Įven today, deep blue, purple and crimson are traditionally associated with royalty, luxury and wealth. In ancient Egypt, only one boat had a purple-dyed sail. Learn about its fascinating history and how you can extract it at school. What links your jeans, sea snails, woad plants and the Egyptian royal family? It’s the dye, indigo.
0 kommentar(er)
