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प्रश्न
What is chromatography ? State its two applications.
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उत्तर
Chromatography is a technique used for separating two or more dissolved solids, which are present in the solution in small quantities.
Separation is based on the fact that two or more substances are soluble in the solvent but their solubility is different.
This technique has various important applications:
- To separate dyes present in black ink
- It is used in forensic science to detect and identify the trace amounts of poison present in the stomach.
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संबंधित प्रश्न
Fill in the blank :
The state of matter with definite volume and definite shape is called______
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arble, Air, Gold, Brass, Sand, Diamond, Graphite, Petroleum, Common salt, Sea-water, Chalk
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A colloid is a ..............mixture and its components can be separated by the technique known as ...............
Define solubility of a substance. How does it vary with temperature ?
When the solid A is added to water, it dissolves with the evolution of a lot of heat and making little explosions to form two products B and C. The properties of products B and C are entirely different from those of solid A as well as water. Moreover, products B and C cannot be reconverted into solid A and water. When another solid D is added to water, it dissolves with the absorption of a little heat to form a product E which cools down. The product E shows the properties of both, solid D as well as water. Moreover, product E can be converted into solid D and water.
(a) What type of change occurs when solid A is dissolved in water ? Why ?
(b) What type of change occurs when solid D is dissolved in water ? Why ?
(c) Name a metal which you think could behave like solid A. Also name the products B and C.
(d) Name the solid D if it is the one which is used in making ordinary dry cells.
(e) Name the process by which D can be recovered from E.
The solubility of ammonium chloride in water at various temperatures is given below :
| Temperature | : | 10°C | 20°C | 40°C | 60°C | 80°C |
| Solubility | : | 24 g | 37 g | 41 g | 55 g | 66 g |
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Justify your answer.
| Figure 1 | Figure 2 | Figure 3 |
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- Which state is represented by Fig. 1?
- In which state will the inter-particle attraction be maximum?
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