Indigo Lab Intro - cloth blue. This type of dyeing is...

Info iconThis preview shows pages 1–2. Sign up to view the full content.

View Full Document Right Arrow Icon
Indigo Lab
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Introduction The overall purpose of this lab is to create a sample of indigo dye and to use it to dye multiple pieces of material. Chemical synthesis, the process of making indigo, consists of using several reagents to create a certain molecule. Indigo’s insolubility in water makes it ineffective in the dyeing process. However, if it undergoes a chemical change, it can be used in the dyeing process. Using experimental and theoretical yields generates an overall percent yield for the experiment. Two different forms of indigo will be prepared in this lab: leucoindigo and indigo carmine. The first form of indigo, leucoindigo, is the product of indigo being oxidized by a reducing agent. Cloth is soaked in the leucoindigo, and then removed and dried. When drying the oxygen in the air oxidizes the leucoindigo back to indigo, which leaves the
Background image of page 2
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: cloth blue. This type of dyeing is called vat dyeing and is used mostly on cotton, wool and other fibers. Because leucoindigo is used commonly in vat dyeing, it is presumptuous that it will also be effective in the dyeing process of the pieces of cloth. There is a slightly different process in preparation involving the indigo carmine. The indigo is reacted with sulfuric acid, which in turn, allows it to be water-soluble. Depending on the concentration it is placed into, the indigo adds two, three, or four sulfuric acid units. Afterwards, a percent yield can then be found using spectrophotometric techniques. One common use for indigo carmine is Blue #2 dye. Indigo disulfonic acid is the expected product because it is the most commonly used form....
View Full Document

This note was uploaded on 09/22/2008 for the course CHEM 104B taught by Professor Staff during the Spring '07 term at University of Arizona- Tucson.

Page1 / 2

Indigo Lab Intro - cloth blue. This type of dyeing is...

This preview shows document pages 1 - 2. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online