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प्रश्न
How does it become possible to cause artificial rain by spraying silver iodide on the clouds?
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उत्तर
Clouds carry a charge as they are colloids. Silver iodide AgI being an electrolyte helps in coagulation process between colloidal particles of water in the cloud. Thus it forms bigger raindrops causing artificial rain. AgI is usually sprayed from an aeroplane or remote-controlled rockets.
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संबंधित प्रश्न
Define the following term:
Zeta potential
Define the following terms: Associated colloids
Define the following term : Brownian movement
Explain the term Electrophoresis
A colloidal sol is prepared by the given method in the figure. What is the charge on hydrated ferric oxide colloidal particles formed in the test tube? How is the sol represented?
Which of the following will show Tyndall effect?
What causes brownian motion in colloidal dispersion?
Why does leather get hardened after tanning?
Match the statement given in Column I with the phenomenon given in Column II.
| Column I | Column II |
| (i) Dispersion medium moves in an electric field | (a) Osmosis |
| (ii) Solvent molecules pass through semi permeable membrane towards solvent side |
(b) Electrophoresis |
| (iii) Movement of charged colloidal particles under the influence of applied electric potential towards oppositely charged electrodes |
(c) Electroosmosis |
| (iv) Solvent molecules pass through semi permeable membranes towards solution side |
(d) Reverse osmosis |
Assertion: An ordinary filter paper impregnated with collodion solution stops the flow of colloidal particles.
Reason: Pore size of the filter paper becomes more than the size of colloidal particle.
Give reason for the following:
Lyophilic colloidal solutions are more stable than lyophobic colloidal solutions.
The right option for the statement “Tyndall effect is exhibited by”, is:
What is electrophoresis?
The conditions given below are in the context of observing Tyndall effect in colloidal solutions:
- The diameter of the colloidal particles is comparable to the wavelength of light used.
- The diameter of the colloidal particles is much smaller than the wavelength of light used.
- The diameter of the colloidal particles is much larger than the wavelength of light used.
- 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:
Coagulation value of the electrolytes AlCl3 and NaCl for As2S3 sol are 0.093 and 52 respectively. The No. of times AlCl3 has greater coagulating power than NaCl is ______.
6.84 g Al2(SO4)3 is needed to coagulate 2.5 L of As2S3 sol completely in 2.0 hrs. The coagulation value of Al2 (SO4)3 is ______.
