Chemistry in Your Day : Bleached Blonde

Have you ever bleached your hair? Most home kits for hair bleaching contain hydrogen peroxide (H₂O₂), an excellent oxidizing agent. When applied to hair, hydrogen peroxide oxidizes melanin, the dark pigment that gives hair colour. Once melanin is oxidized, it no longer imparts a dark colour to hair, leaving the hair with the familiar bleached look. 


Hydrogen peroxide also oxidizes other components of hair. For example, protein molecules in hair contain - SH group called thiols. Hydrogen peroxide oxidizes these thiol groups to sulfonic acid groups (SO₃H). The oxidation of thiol groups to sulfonic acid groups causes changes in the proteins that compose hair, making the hair more brittle and easier to tangle. Consequently, people with heavily bleached hair must use conditioners, which contain compounds that form thin, lubricating coatings on individual hair shafts. These coatings prevent tangling and make hair softer and more manageable.


The following is a reaction of hydrogen peroxide with an alkene:


H₂O₂ + C₂H_{4 ->} C₂H₄O + H₂O


Taken from Chemistry: A Molecular Approach by Nivaldo J. Tro

Other Readings:

• Redox: Fundamentals, Processes and Applications
• Introduction to the High Temperature Oxidation of Metals
• Lab-Aids Introduction to Oxidation-Reduction Kit

Chemistry in Your Day : Atoms and Humans

Dear Reader,
Thank you for reading our blog and contributing by comments and suggestions.
We are now commencing a new series called Chemistry in Your Day, this would be a section where we are going to discuss about how chemistry affects our daily life and how certain phenomenon in our life could be explained with chemistry. This series is taken from Chemistry: A Molecular Approach by Nivaldo J. Tro.
We would like to share a little bit of information from this book.

For this edition of CYD, we are going to discuss The Relation of Atoms and Humans

We are all composed of atoms. we get those atoms from the food we eat over the years. Yesterday's cheeseburger contributes to today's skin, muscle, and hair. The carbon atoms in our own bodies have been used by other living organisms before we got them and will be used by still others when we are done with them. In fact, it is likely that at this moment, your body contains some carbon atoms that were at one time part of your chemistry teacher.

The idea that humans are composed of atoms acting in accord with the laws of chemistry and physics has significant implications and raises many important questions. if atoms compose our brains, for example, do they determine our thoughts and emotions? Are our feelings caused by atoms acting according to the laws of chemistry and physics?

Richard Feynman - Physicist

Richard Feynman (1918-1988), a Nobel Prize-winning physicist, asserted The most important hypothesis in all of biology is that everything that animals do, atoms do. In other words, there is nothing that living things do that cannot be understood from the point of view that they are made of atoms acting according to the laws of physics.

Indeed, biology has undergone a revolution throughout the last 50 years, mostly through the investigation of the atomic and molecular basis for human life. Some have seen the atomic view of life as a devaluation of human life. We have always wanted to distinguish ourselves from everything else, and the idea that we are made of the same basic patterns as all other matter takes something away from that distinction, or does it?