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प्रश्न
Give reasons for the following observations: Leather gets hardened after tanning.
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उत्तर
Animal skin (hide) is colloidal in nature and has positively charged particles, whereas tanning consists of negatively charged colloidal particles. When a hide is soaked in tanning, mutual coagulation takes place and as a result, leather gets hardened.
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संबंधित प्रश्न
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(i) Lyophobic sol is protected.
(ii) Lyophilic sol is protected.
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Assertion: Colloidal solutions show colligative properties.
Reason: Colloidal particles are large in size.
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Reason: Brownian motion is responsible for stability of sols.
Define the following term:
Coagulation
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- The refractive indices of the dispersed phase and the dispersion medium are comparable.
- The dispersed phase has a very different refractive index from the dispersion medium.
Choose the most appropriate conditions from the options given below:
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