Question
Explain Bredig’s arc method.
✓
Answer
- Colloidal sols can be prepared by electrical disintegration using Bredig’s arc method.
- This process involves vaporization as well as condensation.
- Colloidal sols of metals such as gold, silver, platinum can be prepared by this method.
- In this method, electric arc is struck between electrodes of metal immersed in the dispersion medium.
- The intense heat produced vapourizes the metal which then condenses to form particles of colloidal sol.
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