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| Interesting Activities -1 |
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| Remove the chlorophyll of a few leaves by keeping them in warm alcohol for some time. Wash in distilled water and cut thin sections. |
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| Experiment-1 |
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| Phosphate |
| Apparatus required: Section of chlorophyll-free leaf, nitric acid, ammonium molybdate, microscope, slides, cover slip |
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| Procedure |
| 1. Prepare acidic solution of ammonium molybdate by dissolving 1 g of it in 10-15 ml of nitric acid. |
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| 2. Take 1-2 drops of this solution on a glass slide and mount the section of chlorophyll-free leaf in it. Observe under the microscope after 30 minutes. |
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| Observation |
| Minute yellow drops with black borders appear. They later change into yellow crystals of ammonium phospho molybdate. |
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| Experiment-2 |
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| Nitrate |
| Apparatus required: Sections of chlorophyll-free leaf, sulphuric acid, diphenylamine, slides, cover slips, microscope. |
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| Procedure |
| 1. Prepare1:1 solution of diphenylamine by addition 0.1 g of it in 10 ml of sulphuric acid. |
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| 2. Put 1-2 drops of the reagent over a glass slide. Place a section of chlorophyll-free leaf in the reagent and observe under the microscope. |
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| Observation |
| Areas of deep blue colour appear. |
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| Experiment-3 |
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| Potassium |
| Apparatus required: Sections of a chlorophyll-free leaf, platinum chloride or picric acid or sodium cobaltnitrate, distilled water, glass slides, cover slips and microscope |
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| Procedure |
| 1. Prepare 10:1 aqueous solution of platinum chloride by dissolving 1 g of the salt in 10 ml of distilled water. |
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| 2. Mount a section of chlorophyll-free leaf in a drop of this solution on a glass slide. |
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| Observation |
| Small octahedral crystals of yellow colour will be seen inside the cells under the microscope. |
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| Experiment-4 |
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| Calcium |
| Apparatus required: Water, 50% sulphuric acid, glass slides, cover slips, microscope, sections of chlorophyll-free leaf, blotting paper and droppers. |
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| Procedure |
| 1. Mount a section of the chlorophyll-free leaf in water. |
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| 2. Place a cover slip over it. |
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| 3. Pour a drop or two of 50% H2SO4 on one side and drain off water from the other side by means of a blotting paper. |
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| Observation |
| Large needle shaped crystals of calcium sulphate are formed in the section. |
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| Experiment-5 |
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| Iron |
| Apparatus required: Sections of a chlorophyll-free leaf, 20% solution of potassium ferrocyanide, dilute HCl, slides, cover slips, microscope, blotting paper and dropper. |
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| Procedure |
| 1. Mount the section of a chlorophyll-free leaf in 20% potassium ferrocyanide. |
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| 2. Keep it lying for 10-15 minutes. |
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| 3. Then add a drop of dilute 5% HCl to the mount. |
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| 4. Again allow the reaction to proceed for a few minutes. |
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| 5. Add distilled water. |
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| Observation |
| The section will show areas of deep blue colour. |
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