Reds and pinks, oranges, yellows, greens, blues, purples, browns, even grays and blacks, these represent a spectrum of colors that we take for granted thanks to synthetic dyes, but once weavers and fabric makers took great pains to extract these colors and fix them to textiles. Dyers made the colors from lichen, henna, rose madder and juniper, saffron and pomegranate, woad and indigo, acacia and pinon trees.
But a chance discovery, as you’ll learn from the Chemistry Now video, made these colors cheaper to obtain and more effective. In 1856, 18-year-old William Henry Perkin was given the assignment of developing a synthetic route for the production of quinine, which previously could only be extracted from the bark of a cinchona tree grown in South America. He was working with coal tar, and reacted it with potassium dichromate. The result was a black precipitate. When cleaning it up, he discovered it left a rich purple color on the cloth he was using, and the rest is history. Or is it chemistry?
We have reached the 13th week of the weekly, online, video series “Chemistry Now,” and chemistry has moved to industry as a source of interesting video and lessons. As we’ve written before, please view the video, try the lessons, and let us know what you think.
Photo: Corey Holms
Through the Chemistry Now series, NSTA and NBC Learn have teamed up with the National Science Foundation (NSF) to create lessons related to common, physical objects in our world and the changes they undergo every day. The series also looks at the lives and work of scientists on the frontiers of 21st century chemistry.
Video: An 18-year-old London chemistry student tries to make synthetic quinine for malaria treatment, and instead creates the first synthetic dye. View a video that tells the story of the 1856 Chance Discovery that transformed the textile industry worldwide. NBC Learn also profiles a 21st century chemist, Purdue’s Mary Wirth, whose nanomaterials research makes cancer “markers” easier to detect in blood tests.
Middle school lesson: in the Dye Chemistry, students use natural dyes to carry out an investigation to determine which natural products will produce the desired color on eggs or fabric.
High school lesson: the Natural pH Indicators lesson uses household solutions to teach about pH indicators, pH, and properties of acids and bases.
You can use the following form to e-mail us edited versions of the lesson plans:
[contact-form 2 “ChemNow]