✔ 最佳答案
Chromophores are the part of a molecule responsible for the colors we see . When a molecule is exposed to light which is a form of energy , will stimulate the chromophore . This part of molecule will change shape . In many pigments , the chromophores contain alternating single & double bonds . Light excites electrons which move between the orbibitals created by these bonds . The spectrum reflect to our eyes to be identified to be certain color . However bleach does oxidize the structure of chromophore damaging the bonding so when it absorbs light , the excitation is completely different so the reflected light will stimulate our eyes to visualize as white even though the dirty black is still there !
2010-06-07 18:22:21 補充:
The molecule is changed so after use bleach , it is irreversible reaction . You cannot convert back to the original color !!!
2010-06-09 17:12:08 補充:
This is the simple way to explain why after oxidation , the arrangment of the double bonds or single bonds varied so the reflected spectrum changed . The end result our eyes see the color is white .