What do you want to know about bleaching?
Time for fun?
|There are many things one can do with bleaches. As a bleach is a chemical
substance by itself, many things and experiments can be done by just using household
this is possible due to the chemical properties of bleach.
Here are some experiments one can conduct
Galvanized Tacks, Drugstore Iodine, and Household Bleach Materials 1. Galvanized Tacks 2. Iodine 3. Glass cups 4. Liquid household bleach 5. Vinegar Procedure
The iodine solution covering the tacks now has the very dark, purple violet colour of the elemental iodine itself. But if you leave the solution for about half an hour, you will see the liquid slowly fading to a pale yellow or losing its colour completely.
à Immediately the very dark purple of the iodine returns.
à The vinegar causes the lumps to dissolve, producing a dark solution which looks very much like the iodine solution.
Both the loss of colour from the iodine solution and the regeneration of the original colour take place due to a redox reaction. In reducing the purple iodine to colourless iodide ions, the zinc metal acts as a reducing agent and transfers its electrons to iodine molecules.
I2+ Znà Zn2+ + 2I-
In restoring the colour, the solution of bleach, which contains a reserve of ClO-, oxidises the colourless iodide ions back to purple iodine molecules.
The clumps that form appears because hydroxide ions of the basic liquid bleach react with zinc ions to produce insoluble zinc hydroxide, which isnt soluble in water. The acetic acid of the added vinegar reverses the process:
Zn(OH)2+ 2CH3CO2Hà Zn2++ 2CH3CO2- +2H2O
Vitamin C, Drugstore Iodine, and Household Bleach Materials: A glass jar
It might seem to be magic but it is actually redox in action again. Vitamin C is an organic compound, which can be oxidised easily, and so makes a good reducing agent. The redox reaction converts the I2 into colourless I-, just like the first experiment with the household bleach. Vitamin C is used as a sacrificial antioxidant in protecting some foods against oxidation. It acts much like zinc and other metals with reducing properties.
This example of everyday chemistry works well for removing iodine stains from clothing and similar articles using household bleaches. But be careful not to touch the fabric until you rinse out the residual I-. The bleach can reoxidise any remaining I- to I2. It is best to rinse the area thoroughly immediately after the stain is removed.
A small lump of hair
Household liquid bleach
Small glass jar
Foam forms on the surface of the bleach and small bubbles are seen on the hair. The hair is partially or completely dissolved!
Bleach is a basic chemical and hair in an acid. The neutralisation reaction between an acid and a base produces a salt and water. Since bleach can dissolve any fiber that has acidic properties, it is used on cotton because cotton is basic. However, it will dissolve acidic wool due to neutralisation.
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Last modified: 4/7/99