Question

How does oxidising bleach work?

Answer 1

i) The oxidising agents are those molecules which have a tendency of getting reduced.
ii) The role of bleach is to absorb the electrons present in a molecule or alter the bonds which are responsible for the colour of the compound.

Complete step-by-step answer:
The term oxidising bleach means that the substance is an oxidising agent and has bleaching properties as well. Due to the strong oxidising properties of chlorine and sodium hypochlorite, they act as bleaches as they have the ability to break the bonds between the molecules of organic compounds.

Bleaches are known to be strong oxidising agents, which are the compounds which get reduced easily. The role of these oxidising agents is to take the electrons from compounds or chemicals which are responsible for the colour possessed by different materials.

As we know that distinct molecules especially the bonds which are present in the molecules absorb light of different frequencies of the white light which is being incident on the molecule. When these absorbed frequencies having specific colours are absorbed, which are removed from the white light because of the process, the radiation that reflects back from the molecule is observed to have the complimentary colour of the absorbed frequency.

For instance, suppose a molecule absorbs the light of red colour, from the beam of white light, the substance is bound to appear green to us, as the light of that frequency is not absorbed instead it returns back to the viewers’ eyes, without the frequency of the red from white light.

Hence, the colour of a substance possessed by it, is the function of chemical bonds present in the molecule. The bleach is known to change the pattern of bonds within a molecule, which makes it unable to absorb the specific frequency which falls on the visible spectrum, which was responsible for its colour.

On the other hand, the oxidising agents have the ability to alter the bonds present in a material in a way that the material would undergo breaking of its bonds. This phenomena can be generally observed in the bleaching stains from clothing materials.

Note: The bleaches have the tendency to destroy the pigments of a molecule which are responsible for the colour absorption of the molecule, as it breaks the bonds present in a molecule once it is added to it, hence the colour of the substance becomes white.